Introduce explicit config

config/config.go

@@ -0,0 +1,129 @@
+package config
+
+import (
+	"encoding/hex"
+	"fmt"
+	"net"
+	"strconv"
+	"time"
+
+	"github.com/juju/errors"
+)
+
+type Config struct {
+	Debug    bool
+	Verbose  bool
+	BindIP   net.IP
+	BindPort uint16
+
+	PublicIPv4     net.IP
+	PublicIPv4Port uint16
+	PublicIPv6     net.IP
+	PublicIPv6Port uint16
+
+	StatsIP   net.IP
+	StatsPort uint16
+
+	TimeoutRead  time.Duration
+	TimeoutWrite time.Duration
+
+	Secret []byte
+}
+
+type URLs struct {
+	TG        string `json:"tg_url"`
+	TMe       string `json:"tme_url"`
+	TGQRCode  string `json:"tg_qrcode"`
+	TMeQRCode string `json:"tme_qrcode"`
+}
+
+type IPURLs struct {
+	IPv4 URLs `json:"ipv4"`
+	IPv6 URLs `json:"ipv6"`
+}
+
+func (c *Config) BindAddr() string {
+	return getAddr(c.BindIP, c.BindPort)
+}
+
+func (c *Config) IPv4Addr() string {
+	return getAddr(c.PublicIPv4, c.PublicIPv4Port)
+}
+
+func (c *Config) IPv6Addr() string {
+	return getAddr(c.PublicIPv6, c.PublicIPv6Port)
+}
+
+func (c *Config) StatAddr() string {
+	return getAddr(c.StatsIP, c.StatsPort)
+}
+
+func (c *Config) GetURLs() IPURLs {
+	return IPURLs{
+		IPv4: getURLs(c.PublicIPv4, c.PublicIPv4Port, c.Secret),
+		IPv6: getURLs(c.PublicIPv6, c.PublicIPv6Port, c.Secret),
+	}
+}
+
+func getAddr(host fmt.Stringer, port uint16) string {
+	return net.JoinHostPort(host.String(), strconv.Itoa(int(port)))
+}
+
+func NewConfig(debug, verbose bool,
+	bindIP net.IP, bindPort uint16,
+	publicIPv4 net.IP, PublicIPv4Port uint16,
+	publicIPv6 net.IP, publicIPv6Port uint16,
+	statsIP net.IP, statsPort uint16,
+	timeoutRead, timeoutWrite time.Duration,
+	secret string) (*Config, error) {
+	secretBytes, err := hex.DecodeString(secret)
+	if err != nil {
+		return nil, errors.Annotate(err, "Cannot create config")
+	}
+
+	if publicIPv4 == nil {
+		publicIPv4, err = getGlobalIPv4()
+		if err != nil {
+			return nil, errors.Errorf("Cannot get public IP")
+		}
+	}
+	if publicIPv4.To4() == nil {
+		return nil, errors.Errorf("IP %s is not IPv4", publicIPv4.String())
+	}
+	if PublicIPv4Port == 0 {
+		PublicIPv4Port = bindPort
+	}
+
+	if publicIPv6 == nil {
+		publicIPv6, err = getGlobalIPv6()
+		if err != nil {
+			publicIPv6 = publicIPv4
+		}
+	}
+	if publicIPv6.To16() == nil {
+		return nil, errors.Errorf("IP %s is not IPv6", publicIPv6.String())
+	}
+	if publicIPv6Port == 0 {
+		publicIPv6Port = bindPort
+	}
+
+	if statsIP == nil {
+		statsIP = publicIPv4
+	}
+
+	conf := &Config{
+		Debug:          debug,
+		Verbose:        verbose,
+		BindIP:         bindIP,
+		BindPort:       bindPort,
+		PublicIPv4:     publicIPv4,
+		PublicIPv4Port: PublicIPv4Port,
+		PublicIPv6:     publicIPv6,
+		PublicIPv6Port: publicIPv6Port,
+		TimeoutRead:    timeoutRead,
+		TimeoutWrite:   timeoutWrite,
+		Secret:         secretBytes,
+	}
+
+	return conf, nil
+}

config/global_ips.go

@@ -0,0 +1,38 @@
+package config
+
+import (
+	"io/ioutil"
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/juju/errors"
+)
+
+func getGlobalIPv4() (net.IP, error) {
+	return fetchIP("https://v4.ifconfig.co/ip")
+}
+
+func getGlobalIPv6() (net.IP, error) {
+	return fetchIP("https://v6.ifconfig.co/ip")
+}
+
+func fetchIP(url string) (net.IP, error) {
+	resp, err := http.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	respData, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	ip := net.ParseIP(strings.TrimSpace(string(respData)))
+	if ip == nil {
+		return nil, errors.Errorf("ifconfig.co returns incorrect IP %s", resp)
+	}
+
+	return ip, nil
+}

config/urls.go

@@ -0,0 +1,59 @@
+package config
+
+import (
+	"encoding/hex"
+	"net"
+	"net/url"
+	"strconv"
+)
+
+func getURLs(addr net.IP, port uint16, secret []byte) (urls URLs) {
+	values := url.Values{}
+	values.Set("server", addr.String())
+	values.Set("port", strconv.Itoa(int(port)))
+	values.Set("secret", hex.EncodeToString(secret))
+
+	urls.TG = makeTGURL(values)
+	urls.TMe = makeTGURL(values)
+	urls.TGQRCode = makeQRCodeURL(urls.TG)
+	urls.TMeQRCode = makeQRCodeURL(urls.TG)
+
+	return
+}
+
+func makeTGURL(values url.Values) string {
+	tgURL := url.URL{
+		Scheme:   "tg",
+		Host:     "proxy",
+		RawQuery: values.Encode(),
+	}
+
+	return tgURL.String()
+}
+
+func makeTMeURL(values url.Values) string {
+	tMeURL := url.URL{
+		Scheme:   "https",
+		Host:     "t.me",
+		Path:     "proxy",
+		RawQuery: values.Encode(),
+	}
+
+	return tMeURL.String()
+}
+
+func makeQRCodeURL(data string) string {
+	QRURL := url.URL{
+		Scheme: "https",
+		Host:   "api.qrserver.com",
+		Path:   "v1/create-qr-code",
+	}
+
+	values := url.Values{}
+	values.Set("qzone", "4")
+	values.Set("format", "svg")
+	values.Set("data", data)
+	QRURL.RawQuery = values.Encode()
+
+	return QRURL.String()
+}

main.go

@@ -3,18 +3,16 @@ package main
 //go:generate scripts/generate_version.sh
 
 import (
-	"encoding/hex"
 	"encoding/json"
 	"io"
-	"io/ioutil"
-	"net/http"
 	"os"
-	"strings"
 
-	"github.com/9seconds/mtg/proxy"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 	kingpin "gopkg.in/alecthomas/kingpin.v2"
+
+	"github.com/9seconds/mtg/config"
+	"github.com/9seconds/mtg/proxy"
 )
 
 var (
@@ -28,8 +26,9 @@ var (
 		Short('v').
 		Envar("MTG_VERBOSE").
 		Bool()
+
 	bindIP = app.Flag("bind-ip", "Which IP to bind to.").
-		Short('i').
+		Short('b').
 		Envar("MTG_IP").
 		Default("127.0.0.1").
 		IP()
@@ -38,11 +37,23 @@ var (
 			Envar("MTG_PORT").
 			Default("3128").
 			Uint16()
-	portToShow = app.Flag("show-bind-port",
-		"Which port to show in URL. Default is the value of bind-port").
-		Short('a').
-		Envar("MTG_SHOW_PORT").
-		Uint16()
+
+	publicIPv4 = app.Flag("public-ipv4", "Which IPv4 address is public.").
+			Short('4').
+			Envar("MTG_IPV4").
+			IP()
+	publicIPv4Port = app.Flag("public-ipv4-port", "Which IPv4 port is public. Default is 'bind-port' value.").
+			Envar("MTG_IPV4_PORT").
+			Uint16()
+
+	publicIPv6 = app.Flag("public-ipv6", "Which IPv6 address is public.").
+			Short('6').
+			Envar("MTG_IPV6").
+			IP()
+	publicIPv6Port = app.Flag("public-ipv6-port", "Which IPv6 port is public. Default is 'bind-port' value.").
+			Envar("MTG_IPV6_PORT").
+			Uint16()
+
 	statsIP = app.Flag("stats-ip", "Which IP bind stats server to").
 		Short('t').
 		Envar("MTG_STATS_IP").
@@ -53,6 +64,7 @@ var (
 			Envar("MTG_STATS_PORT").
 			Default("3129").
 			Uint16()
+
 	readTimeout = app.Flag("read-timeout", "Socket read timeout.").
 			Short('r').
 			Envar("MTG_READ_TIMEOUT").
@@ -63,15 +75,6 @@ var (
 			Envar("MTG_WRITE_TIMEOUT").
 			Default("30s").
 			Duration()
-	serverName = app.Flag("server-name",
-		"Which server name to use. Default is IP address resolved by ipify.").
-		Short('s').
-		Envar("MTG_SERVER").
-		String()
-	preferIPv6 = app.Flag("prefer-ipv6", "Use IPv6").
-			Short('6').
-			Envar("MTG_USE_IPV6").
-			Bool()
 
 	secret = app.Arg("secret", "Secret of this proxy.").Required().String()
 )
@@ -80,33 +83,22 @@ func main() {
 	app.Version(version)
 	kingpin.MustParse(app.Parse(os.Args[1:]))
 
-	secretBytes, err := hex.DecodeString(*secret)
+	conf, err := config.NewConfig(*debug, *verbose,
+		*bindIP, *bindPort,
+		*publicIPv4, *publicIPv4Port,
+		*publicIPv6, *publicIPv6Port,
+		*statsIP, *statsPort,
+		*readTimeout, *writeTimeout,
+		*secret,
+	)
 	if err != nil {
-		usage("Secret has to be hexadecimal string.")
-	}
-
-	if *portToShow == 0 {
-		*portToShow = *bindPort
-	}
-
-	if *serverName == "" {
-		resp, err := http.Get("https://api.ipify.org")
-		if err != nil || resp.StatusCode != http.StatusOK {
-			usage("Cannot get local IP address.")
-		}
-		myIPBytes, err := ioutil.ReadAll(resp.Body)
-		resp.Body.Close() // nolint: errcheck
-
-		if err != nil {
-			usage("Cannot get local IP address.")
-		}
-		*serverName = strings.TrimSpace(string(myIPBytes))
+		usage(err.Error())
 	}
 
 	atom := zap.NewAtomicLevel()
-	if *debug {
+	if conf.Debug {
 		atom.SetLevel(zapcore.DebugLevel)
-	} else if *verbose {
+	} else if conf.Verbose {
 		atom.SetLevel(zapcore.InfoLevel)
 	} else {
 		atom.SetLevel(zapcore.ErrorLevel)
@@ -118,12 +110,12 @@ func main() {
 		atom,
 	)).Sugar()
 
-	stat := proxy.NewStats(*serverName, *portToShow, *secret)
-	go stat.Serve(*statsIP, *statsPort)
-	printURLs(stat.URLs)
+	stat := proxy.NewStats(conf)
+	go stat.Serve()
+
+	srv := proxy.NewServer(conf, logger, stat)
+	printURLs(conf.GetURLs())
 
-	srv := proxy.NewServer(*bindIP, int(*bindPort), secretBytes, logger,
-		*readTimeout, *writeTimeout, *preferIPv6, stat)
 	if err := srv.Serve(); err != nil {
 		logger.Fatal(err.Error())
 	}

proxy/server.go

@@ -4,34 +4,27 @@ import (
 	"context"
 	"io"
 	"net"
-	"strconv"
 	"sync"
-	"time"
 
-	"github.com/9seconds/mtg/obfuscated2"
-	"github.com/9seconds/mtg/wrappers"
 	"github.com/juju/errors"
 	uuid "github.com/satori/go.uuid"
 	"go.uber.org/zap"
+
+	"github.com/9seconds/mtg/config"
+	"github.com/9seconds/mtg/obfuscated2"
+	"github.com/9seconds/mtg/wrappers"
 )
 
 // Server is an insgtance of MTPROTO proxy.
 type Server struct {
-	ip           net.IP
-	port         int
-	secret       []byte
-	logger       *zap.SugaredLogger
-	ctx          context.Context
-	readTimeout  time.Duration
-	writeTimeout time.Duration
-	stats        *Stats
-	ipv6         bool
+	conf   *config.Config
+	logger *zap.SugaredLogger
+	stats  *Stats
 }
 
 // Serve does MTPROTO proxying.
 func (s *Server) Serve() error {
-	addr := net.JoinHostPort(s.ip.String(), strconv.Itoa(s.port))
-	lsock, err := net.Listen("tcp", addr)
+	lsock, err := net.Listen("tcp", s.conf.BindAddr())
 	if err != nil {
 		return errors.Annotate(err, "Cannot create listen socket")
 	}
@@ -57,10 +50,9 @@ func (s *Server) accept(conn net.Conn) {
 
 	s.stats.newConnection()
 	ctx, cancel := context.WithCancel(context.Background())
-	socketID := s.makeSocketID()
+	socketID := uuid.NewV4().String()
 
 	s.logger.Debugw("Client connected",
-		"secret", s.secret,
 		"addr", conn.RemoteAddr().String(),
 		"socketid", socketID,
 	)
@@ -68,7 +60,6 @@ func (s *Server) accept(conn net.Conn) {
 	clientConn, dc, err := s.getClientStream(ctx, cancel, conn, socketID)
 	if err != nil {
 		s.logger.Warnw("Cannot initialize client connection",
-			"secret", s.secret,
 			"addr", conn.RemoteAddr().String(),
 			"socketid", socketID,
 			"error", err,
@@ -101,25 +92,20 @@ func (s *Server) accept(conn net.Conn) {
 	wait.Wait()
 
 	s.logger.Debugw("Client disconnected",
-		"secret", s.secret,
 		"addr", conn.RemoteAddr().String(),
 		"socketid", socketID,
 	)
 }
 
-func (s *Server) makeSocketID() string {
-	return uuid.NewV4().String()
-}
-
 func (s *Server) getClientStream(ctx context.Context, cancel context.CancelFunc, conn net.Conn, socketID string) (io.ReadWriteCloser, int16, error) {
-	wConn := wrappers.NewTimeoutRWC(conn, s.readTimeout, s.writeTimeout)
+	wConn := wrappers.NewTimeoutRWC(conn, s.conf.TimeoutRead, s.conf.TimeoutWrite)
 	wConn = wrappers.NewTrafficRWC(wConn, s.stats.addIncomingTraffic, s.stats.addOutgoingTraffic)
 	frame, err := obfuscated2.ExtractFrame(wConn)
 	if err != nil {
 		return nil, 0, errors.Annotate(err, "Cannot create client stream")
 	}
 
-	obfs2, dc, err := obfuscated2.ParseObfuscated2ClientFrame(s.secret, frame)
+	obfs2, dc, err := obfuscated2.ParseObfuscated2ClientFrame(s.conf.Secret, frame)
 	if err != nil {
 		return nil, 0, errors.Annotate(err, "Cannot create client stream")
 	}
@@ -132,11 +118,11 @@ func (s *Server) getClientStream(ctx context.Context, cancel context.CancelFunc,
 }
 
 func (s *Server) getTelegramStream(ctx context.Context, cancel context.CancelFunc, dc int16, socketID string) (io.ReadWriteCloser, error) {
-	socket, err := dialToTelegram(s.ipv6, dc, s.readTimeout)
+	socket, err := dialToTelegram(dc, s.conf.TimeoutRead)
 	if err != nil {
 		return nil, errors.Annotate(err, "Cannot dial")
 	}
-	wConn := wrappers.NewTimeoutRWC(socket, s.readTimeout, s.writeTimeout)
+	wConn := wrappers.NewTimeoutRWC(socket, s.conf.TimeoutRead, s.conf.TimeoutWrite)
 	wConn = wrappers.NewTrafficRWC(wConn, s.stats.addIncomingTraffic, s.stats.addOutgoingTraffic)
 
 	obfs2, frame := obfuscated2.MakeTelegramObfuscated2Frame()
@@ -152,17 +138,10 @@ func (s *Server) getTelegramStream(ctx context.Context, cancel context.CancelFun
 }
 
 // NewServer creates new instance of MTPROTO proxy.
-func NewServer(ip net.IP, port int, secret []byte, logger *zap.SugaredLogger,
-	readTimeout, writeTimeout time.Duration, ipv6 bool, stat *Stats) *Server {
+func NewServer(conf *config.Config, logger *zap.SugaredLogger, stat *Stats) *Server {
 	return &Server{
-		ip:           ip,
-		port:         port,
-		secret:       secret,
-		ctx:          context.Background(),
-		logger:       logger,
-		readTimeout:  readTimeout,
-		writeTimeout: writeTimeout,
-		stats:        stat,
-		ipv6:         ipv6,
+		conf:   conf,
+		logger: logger,
+		stats:  stat,
 	}
 }

proxy/stats.go

@@ -2,13 +2,12 @@ package proxy
 
 import (
 	"encoding/json"
-	"fmt"
-	"net"
 	"net/http"
-	"net/url"
 	"strconv"
 	"sync/atomic"
 	"time"
+
+	"github.com/9seconds/mtg/config"
 )
 
 type statsUptime time.Time
@@ -26,13 +25,10 @@ type Stats struct {
 		Incoming uint64 `json:"incoming"`
 		Outgoing uint64 `json:"outgoing"`
 	} `json:"traffic"`
-	URLs struct {
-		TG        string `json:"tg_url"`
-		TMe       string `json:"tme_url"`
-		TGQRCode  string `json:"tg_qrcode"`
-		TMeQRCode string `json:"tme_qrcode"`
-	} `json:"urls"`
-	Uptime statsUptime `json:"uptime"`
+	URLs   config.IPURLs `json:"urls"`
+	Uptime statsUptime   `json:"uptime"`
+
+	conf *config.Config
 }
 
 func (s *Stats) newConnection() {
@@ -53,7 +49,7 @@ func (s *Stats) addOutgoingTraffic(n int) {
 }
 
 // Serve runs statistics HTTP server.
-func (s *Stats) Serve(host fmt.Stringer, port uint16) {
+func (s *Stats) Serve() {
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
 
@@ -63,65 +59,16 @@ func (s *Stats) Serve(host fmt.Stringer, port uint16) {
 		encoder.Encode(s) // nolint: errcheck, gas
 	})
 
-	addr := net.JoinHostPort(host.String(), strconv.Itoa(int(port)))
-	http.ListenAndServe(addr, nil) // nolint: errcheck, gas
+	http.ListenAndServe(s.conf.StatAddr(), nil) // nolint: errcheck, gas
 }
 
 // NewStats returns new instance of statistics datastructure.
-func NewStats(serverName string, port uint16, secret string) *Stats {
-	urlQuery := makeURLQuery(serverName, port, secret)
-
-	stat := &Stats{Uptime: statsUptime(time.Now())}
-	stat.URLs.TG = makeTGURL(urlQuery)
-	stat.URLs.TMe = makeTMeURL(urlQuery)
-	stat.URLs.TGQRCode = makeQRCodeURL(stat.URLs.TG)
-	stat.URLs.TMeQRCode = makeQRCodeURL(stat.URLs.TMe)
-
-	return stat
-}
-
-func makeURLQuery(serverName string, port uint16, secret string) url.Values {
-	values := url.Values{}
-	values.Set("server", serverName)
-	values.Set("port", strconv.Itoa(int(port)))
-	values.Set("secret", secret)
-
-	return values
-}
-
-func makeTGURL(values url.Values) string {
-	tgURL := url.URL{
-		Scheme:   "tg",
-		Host:     "proxy",
-		RawQuery: values.Encode(),
+func NewStats(conf *config.Config) *Stats {
+	stat := &Stats{
+		Uptime: statsUptime(time.Now()),
+		conf:   conf,
 	}
+	stat.URLs = conf.GetURLs()
 
-	return tgURL.String()
-}
-
-func makeTMeURL(values url.Values) string {
-	tMeURL := url.URL{
-		Scheme:   "https",
-		Host:     "t.me",
-		Path:     "proxy",
-		RawQuery: values.Encode(),
-	}
-
-	return tMeURL.String()
-}
-
-func makeQRCodeURL(data string) string {
-	QRURL := url.URL{
-		Scheme: "https",
-		Host:   "api.qrserver.com",
-		Path:   "v1/create-qr-code",
-	}
-
-	values := url.Values{}
-	values.Set("qzone", "4")
-	values.Set("format", "svg")
-	values.Set("data", data)
-	QRURL.RawQuery = values.Encode()
-
-	return QRURL.String()
+	return stat
 }

proxy/telegram.go

@@ -37,12 +37,12 @@ const telegramPort = "443"
 
 const telegramKeepAlive = 30 * time.Second
 
-func dialToTelegram(ipv6 bool, dcIdx int16, timeout time.Duration) (net.Conn, error) {
+func dialToTelegram(dcIdx int16, timeout time.Duration) (net.Conn, error) {
 	if dcIdx < 0 || dcIdx >= 5 {
 		return nil, errors.New("Incorrect DC IDX")
 	}
 
-	conn, err := doDial(ipv6, dcIdx, timeout)
+	conn, err := doDial(dcIdx, timeout)
 	if err != nil {
 		return nil, errors.Annotate(err, "Cannot dial")
 	}
@@ -57,14 +57,12 @@ func dialToTelegram(ipv6 bool, dcIdx int16, timeout time.Duration) (net.Conn, er
 	return conn, nil
 }
 
-func doDial(ipv6 bool, dcIdx int16, timeout time.Duration) (*net.TCPConn, error) {
+func doDial(dcIdx int16, timeout time.Duration) (*net.TCPConn, error) {
 	dialer := net.Dialer{Timeout: timeout}
 	addr := TelegramAddresses[dcIdx]
 
-	if ipv6 {
-		if conn, err := dialer.Dial("tcp", addr.IPv6()); err == nil {
-			return conn.(*net.TCPConn), nil
-		}
+	if conn, err := dialer.Dial("tcp", addr.IPv6()); err == nil {
+		return conn.(*net.TCPConn), nil
 	}
 
 	conn, err := dialer.Dial("tcp", addr.IPv4())