Merge pull request 'refactor' (#22) from refactor into staging

Reviewed-on: bagas/tunnl_please#22

server/http.go

@@ -11,6 +11,7 @@ import (
 	"regexp"
 	"strings"
 	"tunnel_pls/session"
+	"tunnel_pls/session/interaction"
 	"tunnel_pls/utils"
 
 	"golang.org/x/crypto/ssh"
@@ -29,12 +30,16 @@ type CustomWriter struct {
 	buf         []byte
 	respHeader  *ResponseHeaderFactory
 	reqHeader   *RequestHeaderFactory
-	interaction *session.Interaction
+	interaction interaction.Controller
 	respMW      []ResponseMiddleware
 	reqStartMW  []RequestMiddleware
 	reqEndMW    []RequestMiddleware
 }
 
+func (cw *CustomWriter) SetInteraction(interaction interaction.Controller) {
+	cw.interaction = interaction
+}
+
 func (cw *CustomWriter) Read(p []byte) (int, error) {
 	tmp := make([]byte, len(p))
 	read, err := cw.reader.Read(tmp)
@@ -177,7 +182,7 @@ func (cw *CustomWriter) Write(p []byte) (int, error) {
 	return n, nil
 }
 
-func (cw *CustomWriter) AddInteraction(interaction *session.Interaction) {
+func (cw *CustomWriter) AddInteraction(interaction *interaction.Interaction) {
 	cw.interaction = interaction
 }
 
@@ -287,16 +292,15 @@ func Handler(conn net.Conn) {
 		return
 	}
 	cw := NewCustomWriter(conn, dstReader, conn.RemoteAddr())
-
+	cw.SetInteraction(sshSession.Interaction)
 	forwardRequest(cw, reqhf, sshSession)
 	return
 }
 
 func forwardRequest(cw *CustomWriter, initialRequest *RequestHeaderFactory, sshSession *session.SSHSession) {
-	cw.AddInteraction(sshSession.Interaction)
 	originHost, originPort := ParseAddr(cw.RemoteAddr.String())
 	payload := createForwardedTCPIPPayload(originHost, uint16(originPort), sshSession.Forwarder.GetForwardedPort())
-	channel, reqs, err := sshSession.Conn.OpenChannel("forwarded-tcpip", payload)
+	channel, reqs, err := sshSession.Lifecycle.GetConnection().OpenChannel("forwarded-tcpip", payload)
 	if err != nil {
 		log.Printf("Failed to open forwarded-tcpip channel: %v", err)
 		sendBadGatewayResponse(cw)
@@ -346,7 +350,7 @@ func forwardRequest(cw *CustomWriter, initialRequest *RequestHeaderFactory, sshS
 		}
 	}
 
-	sshSession.HandleForwardedConnection(cw, channel, cw.RemoteAddr)
+	sshSession.Forwarder.HandleConnection(cw, channel, cw.RemoteAddr)
 	return
 }
 

server/middleware.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"net"
 	"time"
-	"tunnel_pls/session"
+	"tunnel_pls/session/interaction"
 )
 
 type RequestMiddleware interface {
@@ -29,13 +29,13 @@ func (h *TunnelFingerprint) HandleResponse(header *ResponseHeaderFactory, body [
 }
 
 type RequestLogger struct {
-	interaction session.Interaction
+	interaction interaction.Controller
 	remoteAddr  net.Addr
 }
 
-func NewRequestLogger(interaction *session.Interaction, remoteAddr net.Addr) *RequestLogger {
+func NewRequestLogger(interaction interaction.Controller, remoteAddr net.Addr) *RequestLogger {
 	return &RequestLogger{
-		interaction: *interaction,
+		interaction: interaction,
 		remoteAddr:  remoteAddr,
 	}
 }

session/forwarder.go

@@ -1,37 +0,0 @@
-package session
-
-import (
-	"net"
-
-	"golang.org/x/crypto/ssh"
-)
-
-type Forwarder struct {
-	Listener      net.Listener
-	TunnelType    TunnelType
-	ForwardedPort uint16
-
-	getSlug func() string
-	setSlug func(string)
-}
-
-type ForwardingController interface {
-	HandleGlobalRequest(ch <-chan *ssh.Request)
-	HandleTCPIPForward(req *ssh.Request)
-	HandleHTTPForward(req *ssh.Request, port uint16)
-	HandleTCPForward(req *ssh.Request, addr string, port uint16)
-	AcceptTCPConnections()
-}
-
-type ForwarderInfo interface {
-	GetTunnelType() TunnelType
-	GetForwardedPort() uint16
-}
-
-func (f *Forwarder) GetTunnelType() TunnelType {
-	return f.TunnelType
-}
-
-func (f *Forwarder) GetForwardedPort() uint16 {
-	return f.ForwardedPort
-}

session/forwarder/forwarder.go

@@ -0,0 +1,167 @@
+package forwarder
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"io"
+	"log"
+	"net"
+	"strconv"
+	"tunnel_pls/session/slug"
+	"tunnel_pls/types"
+
+	"golang.org/x/crypto/ssh"
+)
+
+type Forwarder struct {
+	Listener      net.Listener
+	TunnelType    types.TunnelType
+	ForwardedPort uint16
+	SlugManager   slug.Manager
+	Lifecycle     Lifecycle
+}
+
+type Lifecycle interface {
+	GetConnection() ssh.Conn
+}
+
+type ForwardingController interface {
+	AcceptTCPConnections()
+	SetType(tunnelType types.TunnelType)
+	GetTunnelType() types.TunnelType
+	GetForwardedPort() uint16
+	SetForwardedPort(port uint16)
+	SetListener(listener net.Listener)
+	GetListener() net.Listener
+	Close() error
+	HandleConnection(dst io.ReadWriter, src ssh.Channel, remoteAddr net.Addr)
+	SetLifecycle(lifecycle Lifecycle)
+}
+
+func (f *Forwarder) SetLifecycle(lifecycle Lifecycle) {
+	f.Lifecycle = lifecycle
+}
+
+func (f *Forwarder) AcceptTCPConnections() {
+	for {
+		conn, err := f.GetListener().Accept()
+		if err != nil {
+			if errors.Is(err, net.ErrClosed) {
+				return
+			}
+			log.Printf("Error accepting connection: %v", err)
+			continue
+		}
+		originHost, originPort := ParseAddr(conn.RemoteAddr().String())
+		payload := createForwardedTCPIPPayload(originHost, uint16(originPort), f.GetForwardedPort())
+		channel, reqs, err := f.Lifecycle.GetConnection().OpenChannel("forwarded-tcpip", payload)
+		if err != nil {
+			log.Printf("Failed to open forwarded-tcpip channel: %v", err)
+			return
+		}
+
+		go func() {
+			for req := range reqs {
+				err := req.Reply(false, nil)
+				if err != nil {
+					log.Printf("Failed to reply to request: %v", err)
+					return
+				}
+			}
+		}()
+		go f.HandleConnection(conn, channel, conn.RemoteAddr())
+	}
+}
+
+func (f *Forwarder) HandleConnection(dst io.ReadWriter, src ssh.Channel, remoteAddr net.Addr) {
+	defer func(src ssh.Channel) {
+		err := src.Close()
+		if err != nil && !errors.Is(err, io.EOF) {
+			log.Printf("Error closing connection: %v", err)
+		}
+	}(src)
+	log.Printf("Handling new forwarded connection from %s", remoteAddr)
+
+	go func() {
+		_, err := io.Copy(src, dst)
+		if err != nil && !errors.Is(err, io.EOF) && !errors.Is(err, net.ErrClosed) {
+			log.Printf("Error copying from conn.Reader to channel: %v", err)
+		}
+	}()
+
+	_, err := io.Copy(dst, src)
+
+	if err != nil && !errors.Is(err, io.EOF) {
+		log.Printf("Error copying from channel to conn.Writer: %v", err)
+	}
+	return
+}
+
+func (f *Forwarder) SetType(tunnelType types.TunnelType) {
+	f.TunnelType = tunnelType
+}
+
+func (f *Forwarder) GetTunnelType() types.TunnelType {
+	return f.TunnelType
+}
+
+func (f *Forwarder) GetForwardedPort() uint16 {
+	return f.ForwardedPort
+}
+
+func (f *Forwarder) SetForwardedPort(port uint16) {
+	f.ForwardedPort = port
+}
+
+func (f *Forwarder) SetListener(listener net.Listener) {
+	f.Listener = listener
+}
+
+func (f *Forwarder) GetListener() net.Listener {
+	return f.Listener
+}
+
+func (f *Forwarder) Close() error {
+	if f.GetTunnelType() != types.HTTP {
+		return f.Listener.Close()
+	}
+	return nil
+}
+
+func ParseAddr(addr string) (string, uint32) {
+	host, portStr, err := net.SplitHostPort(addr)
+	if err != nil {
+		log.Printf("Failed to parse origin address: %s from address %s", err.Error(), addr)
+		return "0.0.0.0", uint32(0)
+	}
+	port, _ := strconv.Atoi(portStr)
+	return host, uint32(port)
+}
+func writeSSHString(buffer *bytes.Buffer, str string) {
+	err := binary.Write(buffer, binary.BigEndian, uint32(len(str)))
+	if err != nil {
+		log.Printf("Failed to write string to buffer: %v", err)
+		return
+	}
+	buffer.WriteString(str)
+}
+
+func createForwardedTCPIPPayload(host string, originPort, port uint16) []byte {
+	var buf bytes.Buffer
+
+	writeSSHString(&buf, "localhost")
+	err := binary.Write(&buf, binary.BigEndian, uint32(port))
+	if err != nil {
+		log.Printf("Failed to write string to buffer: %v", err)
+		return nil
+	}
+	writeSSHString(&buf, host)
+	err = binary.Write(&buf, binary.BigEndian, uint32(originPort))
+	if err != nil {
+		log.Printf("Failed to write string to buffer: %v", err)
+		return nil
+	}
+
+	return buf.Bytes()
+}

session/handler.go

@@ -3,98 +3,24 @@ package session
 import (
 	"bytes"
 	"encoding/binary"
-	"errors"
 	"fmt"
-	"io"
 	"log"
 	"net"
-	"strconv"
-	"sync"
-	"time"
 	portUtil "tunnel_pls/internal/port"
+	"tunnel_pls/types"
 
 	"tunnel_pls/utils"
 
 	"golang.org/x/crypto/ssh"
 )
 
-type Status string
-
-var forbiddenSlug = []string{
-	"ping",
-}
-
-type UserConnection struct {
-	Reader io.Reader
-	Writer net.Conn
-}
-
-var (
-	clientsMutex sync.RWMutex
-	Clients      = make(map[string]*SSHSession)
-)
-
-func registerClient(slug string, session *SSHSession) bool {
-	clientsMutex.Lock()
-	defer clientsMutex.Unlock()
-
-	if _, exists := Clients[slug]; exists {
-		return false
-	}
-
-	Clients[slug] = session
-	return true
-}
-
-func unregisterClient(slug string) {
-	clientsMutex.Lock()
-	defer clientsMutex.Unlock()
-
-	delete(Clients, slug)
-}
-
-func (s *SSHSession) Close() error {
-	if s.Forwarder.Listener != nil {
-		err := s.Forwarder.Listener.Close()
-		if err != nil && !errors.Is(err, net.ErrClosed) {
-			return err
-		}
-	}
-
-	if s.channel != nil {
-		err := s.channel.Close()
-		if err != nil && !errors.Is(err, io.EOF) {
-			return err
-		}
-	}
-
-	if s.Conn != nil {
-		err := s.Conn.Close()
-		if err != nil && !errors.Is(err, net.ErrClosed) {
-			return err
-		}
-	}
-
-	slug := s.Forwarder.getSlug()
-	if slug != "" {
-		unregisterClient(slug)
-	}
-
-	if s.Forwarder.TunnelType == TCP && s.Forwarder.Listener != nil {
-		err := portUtil.Manager.SetPortStatus(s.Forwarder.ForwardedPort, false)
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
+var blockedReservedPorts = []uint16{1080, 1433, 1521, 1900, 2049, 3306, 3389, 5432, 5900, 6379, 8080, 8443, 9000, 9200, 27017}
 
 func (s *SSHSession) HandleGlobalRequest(GlobalRequest <-chan *ssh.Request) {
 	for req := range GlobalRequest {
 		switch req.Type {
 		case "tcpip-forward":
-			s.handleTCPIPForward(req)
+			s.HandleTCPIPForward(req)
 			return
 		case "shell", "pty-req", "window-change":
 			err := req.Reply(true, nil)
@@ -113,7 +39,7 @@ func (s *SSHSession) HandleGlobalRequest(GlobalRequest <-chan *ssh.Request) {
 	}
 }
 
-func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
+func (s *SSHSession) HandleTCPIPForward(req *ssh.Request) {
 	log.Println("Port forwarding request detected")
 
 	reader := bytes.NewReader(req.Payload)
@@ -126,7 +52,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 			log.Println("Failed to reply to request:", err)
 			return
 		}
-		err = s.Close()
+		err = s.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
@@ -142,7 +68,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 			log.Println("Failed to reply to request:", err)
 			return
 		}
-		err = s.Close()
+		err = s.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
@@ -156,7 +82,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 			log.Println("Failed to reply to request:", err)
 			return
 		}
-		err = s.Close()
+		err = s.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
@@ -172,7 +98,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 			log.Println("Failed to reply to request:", err)
 			return
 		}
-		err = s.Close()
+		err = s.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
@@ -180,11 +106,11 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 	}
 
 	s.Interaction.SendMessage("\033[H\033[2J")
-	s.Lifecycle.Status = RUNNING
+	s.Lifecycle.SetStatus(types.RUNNING)
 	go s.Interaction.HandleUserInput()
 
 	if portToBind == 80 || portToBind == 443 {
-		s.handleHTTPForward(req, portToBind)
+		s.HandleHTTPForward(req, portToBind)
 		return
 	} else {
 		if portToBind == 0 {
@@ -197,7 +123,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 					log.Println("Failed to reply to request:", err)
 					return
 				}
-				err = s.Close()
+				err = s.Lifecycle.Close()
 				if err != nil {
 					log.Printf("failed to close session: %v", err)
 				}
@@ -210,7 +136,7 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 				log.Println("Failed to reply to request:", err)
 				return
 			}
-			err = s.Close()
+			err = s.Lifecycle.Close()
 			if err != nil {
 				log.Printf("failed to close session: %v", err)
 			}
@@ -222,29 +148,12 @@ func (s *SSHSession) handleTCPIPForward(req *ssh.Request) {
 			return
 		}
 	}
-	s.handleTCPForward(req, addr, portToBind)
+	s.HandleTCPForward(req, addr, portToBind)
 }
 
-var blockedReservedPorts = []uint16{1080, 1433, 1521, 1900, 2049, 3306, 3389, 5432, 5900, 6379, 8080, 8443, 9000, 9200, 27017}
-
-func isBlockedPort(port uint16) bool {
-	if port == 80 || port == 443 {
-		return false
-	}
-	if port < 1024 && port != 0 {
-		return true
-	}
-	for _, p := range blockedReservedPorts {
-		if p == port {
-			return true
-		}
-	}
-	return false
-}
-
-func (s *SSHSession) handleHTTPForward(req *ssh.Request, portToBind uint16) {
-	s.Forwarder.TunnelType = HTTP
-	s.Forwarder.ForwardedPort = portToBind
+func (s *SSHSession) HandleHTTPForward(req *ssh.Request, portToBind uint16) {
+	s.Forwarder.SetType(types.HTTP)
+	s.Forwarder.SetForwardedPort(portToBind)
 
 	slug := generateUniqueSlug()
 	if slug == "" {
@@ -256,7 +165,7 @@ func (s *SSHSession) handleHTTPForward(req *ssh.Request, portToBind uint16) {
 		return
 	}
 
-	s.Forwarder.setSlug(slug)
+	s.SlugManager.Set(slug)
 	registerClient(slug, s)
 
 	buf := new(bytes.Buffer)
@@ -282,8 +191,8 @@ func (s *SSHSession) handleHTTPForward(req *ssh.Request, portToBind uint16) {
 	}
 }
 
-func (s *SSHSession) handleTCPForward(req *ssh.Request, addr string, portToBind uint16) {
-	s.Forwarder.TunnelType = TCP
+func (s *SSHSession) HandleTCPForward(req *ssh.Request, addr string, portToBind uint16) {
+	s.Forwarder.SetType(types.TCP)
 	log.Printf("Requested forwarding on %s:%d", addr, portToBind)
 
 	listener, err := net.Listen("tcp", fmt.Sprintf("0.0.0.0:%d", portToBind))
@@ -294,18 +203,18 @@ func (s *SSHSession) handleTCPForward(req *ssh.Request, addr string, portToBind
 			log.Println("Failed to reply to request:", err)
 			return
 		}
-		err = s.Close()
+		err = s.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
 		return
 	}
-	s.Forwarder.Listener = listener
-	s.Forwarder.ForwardedPort = portToBind
+	s.Forwarder.SetListener(listener)
+	s.Forwarder.SetForwardedPort(portToBind)
 	s.Interaction.ShowWelcomeMessage()
-	s.Interaction.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s:%d \r\n", s.Forwarder.TunnelType, utils.Getenv("domain"), s.Forwarder.ForwardedPort))
+	s.Interaction.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s:%d \r\n", s.Forwarder.GetTunnelType(), utils.Getenv("domain"), s.Forwarder.GetForwardedPort()))
 
-	go s.acceptTCPConnections()
+	go s.Forwarder.AcceptTCPConnections()
 
 	buf := new(bytes.Buffer)
 	err = binary.Write(buf, binary.BigEndian, uint32(portToBind))
@@ -321,37 +230,6 @@ func (s *SSHSession) handleTCPForward(req *ssh.Request, addr string, portToBind
 	}
 }
 
-func (s *SSHSession) acceptTCPConnections() {
-	for {
-		conn, err := s.Forwarder.Listener.Accept()
-		if err != nil {
-			if errors.Is(err, net.ErrClosed) {
-				return
-			}
-			log.Printf("Error accepting connection: %v", err)
-			continue
-		}
-		originHost, originPort := ParseAddr(conn.RemoteAddr().String())
-		payload := createForwardedTCPIPPayload(originHost, uint16(originPort), s.Forwarder.GetForwardedPort())
-		channel, reqs, err := s.Conn.OpenChannel("forwarded-tcpip", payload)
-		if err != nil {
-			log.Printf("Failed to open forwarded-tcpip channel: %v", err)
-			return
-		}
-
-		go func() {
-			for req := range reqs {
-				err := req.Reply(false, nil)
-				if err != nil {
-					log.Printf("Failed to reply to request: %v", err)
-					return
-				}
-			}
-		}()
-		go s.HandleForwardedConnection(conn, channel, conn.RemoteAddr())
-	}
-}
-
 func generateUniqueSlug() string {
 	maxAttempts := 5
 
@@ -371,95 +249,6 @@ func generateUniqueSlug() string {
 	return ""
 }
 
-func (s *SSHSession) waitForRunningStatus() {
-	timeout := time.After(3 * time.Second)
-	ticker := time.NewTicker(150 * time.Millisecond)
-	defer ticker.Stop()
-	frames := []string{"-", "\\", "|", "/"}
-	i := 0
-	for {
-		select {
-		case <-ticker.C:
-			s.Interaction.SendMessage(fmt.Sprintf("\rLoading %s", frames[i]))
-			i = (i + 1) % len(frames)
-			if s.Lifecycle.Status == RUNNING {
-				s.Interaction.SendMessage("\r\033[K")
-				return
-			}
-		case <-timeout:
-			s.Interaction.SendMessage("\r\033[K")
-			s.Interaction.SendMessage("TCP/IP request not received in time.\r\nCheck your internet connection and confirm the server responds within 3000ms.\r\nEnsure you ran the correct command. For more details, visit https://tunnl.live.\r\n\r\n")
-			err := s.Close()
-			if err != nil {
-				log.Printf("failed to close session: %v", err)
-			}
-			log.Println("Timeout waiting for session to start running")
-			return
-		}
-	}
-}
-
-func isForbiddenSlug(slug string) bool {
-	for _, s := range forbiddenSlug {
-		if slug == s {
-			return true
-		}
-	}
-	return false
-}
-
-func isValidSlug(slug string) bool {
-	if len(slug) < 3 || len(slug) > 20 {
-		return false
-	}
-
-	if slug[0] == '-' || slug[len(slug)-1] == '-' {
-		return false
-	}
-
-	for _, c := range slug {
-		if !((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '-') {
-			return false
-		}
-	}
-
-	return true
-}
-
-func waitForKeyPress(connection ssh.Channel) {
-	keyBuf := make([]byte, 1)
-	for {
-		_, err := connection.Read(keyBuf)
-		if err == nil {
-			break
-		}
-	}
-}
-
-func (s *SSHSession) HandleForwardedConnection(dst io.ReadWriter, src ssh.Channel, remoteAddr net.Addr) {
-	defer func(src ssh.Channel) {
-		err := src.Close()
-		if err != nil && !errors.Is(err, io.EOF) {
-			log.Printf("Error closing connection: %v", err)
-		}
-	}(src)
-	log.Printf("Handling new forwarded connection from %s", remoteAddr)
-
-	go func() {
-		_, err := io.Copy(src, dst)
-		if err != nil && !errors.Is(err, io.EOF) && !errors.Is(err, net.ErrClosed) {
-			log.Printf("Error copying from conn.Reader to channel: %v", err)
-		}
-	}()
-
-	_, err := io.Copy(dst, src)
-
-	if err != nil && !errors.Is(err, io.EOF) {
-		log.Printf("Error copying from channel to conn.Writer: %v", err)
-	}
-	return
-}
-
 func readSSHString(reader *bytes.Reader) (string, error) {
 	var length uint32
 	if err := binary.Read(reader, binary.BigEndian, &length); err != nil {
@@ -472,40 +261,17 @@ func readSSHString(reader *bytes.Reader) (string, error) {
 	return string(strBytes), nil
 }
 
-func createForwardedTCPIPPayload(host string, originPort, port uint16) []byte {
-	var buf bytes.Buffer
-
-	writeSSHString(&buf, "localhost")
-	err := binary.Write(&buf, binary.BigEndian, uint32(port))
-	if err != nil {
-		log.Printf("Failed to write string to buffer: %v", err)
-		return nil
+func isBlockedPort(port uint16) bool {
+	if port == 80 || port == 443 {
+		return false
 	}
-	writeSSHString(&buf, host)
-	err = binary.Write(&buf, binary.BigEndian, uint32(originPort))
-	if err != nil {
-		log.Printf("Failed to write string to buffer: %v", err)
-		return nil
+	if port < 1024 && port != 0 {
+		return true
 	}
-
-	return buf.Bytes()
-}
-
-func writeSSHString(buffer *bytes.Buffer, str string) {
-	err := binary.Write(buffer, binary.BigEndian, uint32(len(str)))
-	if err != nil {
-		log.Printf("Failed to write string to buffer: %v", err)
-		return
-	}
-	buffer.WriteString(str)
-}
-
-func ParseAddr(addr string) (string, uint32) {
-	host, portStr, err := net.SplitHostPort(addr)
-	if err != nil {
-		log.Printf("Failed to parse origin address: %s from address %s", err.Error(), addr)
-		return "0.0.0.0", uint32(0)
-	}
-	port, _ := strconv.Atoi(portStr)
-	return host, uint32(port)
+	for _, p := range blockedReservedPorts {
+		if p == port {
+			return true
+		}
+	}
+	return false
 }

session/interaction/interaction.go

@@ -1,4 +1,4 @@
-package session
+package interaction
 
 import (
 	"bytes"
@@ -7,21 +7,40 @@ import (
 	"log"
 	"strings"
 	"time"
+	"tunnel_pls/session/slug"
+	"tunnel_pls/types"
 	"tunnel_pls/utils"
 
 	"golang.org/x/crypto/ssh"
 )
 
-type InteractionController interface {
+var forbiddenSlug = []string{
+	"ping",
+}
+
+type Lifecycle interface {
+	Close() error
+}
+
+type Controller interface {
 	SendMessage(message string)
 	HandleUserInput()
-	HandleCommand(conn ssh.Channel, command string, inSlugEditMode *bool, editSlug *string, buf *bytes.Buffer)
-	HandleSlugEditMode(conn ssh.Channel, inSlugEditMode *bool, editSlug *string, char byte, buf *bytes.Buffer)
-	HandleSlugSave(conn ssh.Channel, inSlugEditMode *bool, editSlug *string, buf *bytes.Buffer)
-	HandleSlugCancel(conn ssh.Channel, inSlugEditMode *bool, buf *bytes.Buffer)
+	HandleCommand(command string)
+	HandleSlugEditMode(connection ssh.Channel, char byte)
+	HandleSlugSave(conn ssh.Channel)
+	HandleSlugCancel(connection ssh.Channel)
 	HandleSlugUpdateError()
 	ShowWelcomeMessage()
 	DisplaySlugEditor()
+	SetChannel(channel ssh.Channel)
+	SetLifecycle(lifecycle Lifecycle)
+	SetSlugModificator(func(oldSlug, newSlug string) bool)
+}
+
+type Forwarder interface {
+	Close() error
+	GetTunnelType() types.TunnelType
+	GetForwardedPort() uint16
 }
 
 type Interaction struct {
@@ -29,13 +48,18 @@ type Interaction struct {
 	EditMode         bool
 	EditSlug         string
 	channel          ssh.Channel
+	SlugManager      slug.Manager
+	Forwarder        Forwarder
+	Lifecycle        Lifecycle
+	updateClientSlug func(oldSlug, newSlug string) bool
+}
 
-	getSlug func() string
-	setSlug func(string)
+func (i *Interaction) SetLifecycle(lifecycle Lifecycle) {
+	i.Lifecycle = lifecycle
+}
 
-	session SessionCloser
-
-	forwarder ForwarderInfo
+func (i *Interaction) SetChannel(channel ssh.Channel) {
+	i.channel = channel
 }
 
 func (i *Interaction) SendMessage(message string) {
@@ -49,7 +73,6 @@ func (i *Interaction) SendMessage(message string) {
 }
 
 func (i *Interaction) HandleUserInput() {
-	var commandBuffer bytes.Buffer
 	buf := make([]byte, 1)
 	i.EditMode = false
 
@@ -66,42 +89,42 @@ func (i *Interaction) HandleUserInput() {
 			char := buf[0]
 
 			if i.EditMode {
-				i.HandleSlugEditMode(i.channel, char, &commandBuffer)
+				i.HandleSlugEditMode(i.channel, char)
 				continue
 			}
 
 			i.SendMessage(string(buf[:n]))
 
 			if char == 8 || char == 127 {
-				if commandBuffer.Len() > 0 {
-					commandBuffer.Truncate(commandBuffer.Len() - 1)
+				if i.CommandBuffer.Len() > 0 {
+					i.CommandBuffer.Truncate(i.CommandBuffer.Len() - 1)
 					i.SendMessage("\b \b")
 				}
 				continue
 			}
 
 			if char == '/' {
-				commandBuffer.Reset()
-				commandBuffer.WriteByte(char)
+				i.CommandBuffer.Reset()
+				i.CommandBuffer.WriteByte(char)
 				continue
 			}
 
-			if commandBuffer.Len() > 0 {
+			if i.CommandBuffer.Len() > 0 {
 				if char == 13 {
-					i.HandleCommand(commandBuffer.String(), &commandBuffer)
+					i.HandleCommand(i.CommandBuffer.String())
 					continue
 				}
-				commandBuffer.WriteByte(char)
+				i.CommandBuffer.WriteByte(char)
 			}
 		}
 	}
 }
 
-func (i *Interaction) HandleSlugEditMode(connection ssh.Channel, char byte, commandBuffer *bytes.Buffer) {
+func (i *Interaction) HandleSlugEditMode(connection ssh.Channel, char byte) {
 	if char == 13 {
 		i.HandleSlugSave(connection)
 	} else if char == 27 {
-		i.HandleSlugCancel(connection, commandBuffer)
+		i.HandleSlugCancel(connection)
 	} else if char == 8 || char == 127 {
 		if len(i.EditSlug) > 0 {
 			i.EditSlug = (i.EditSlug)[:len(i.EditSlug)-1]
@@ -142,10 +165,10 @@ func (i *Interaction) HandleSlugSave(connection ssh.Channel) {
 		return
 	}
 	if isValid {
-		oldSlug := i.getSlug()
+		oldSlug := i.SlugManager.Get()
 		newSlug := i.EditSlug
 
-		if !updateClientSlug(oldSlug, newSlug) {
+		if !i.updateClientSlug(oldSlug, newSlug) {
 			i.HandleSlugUpdateError()
 			return
 		}
@@ -223,7 +246,7 @@ func (i *Interaction) HandleSlugSave(connection ssh.Channel) {
 	if utils.Getenv("tls_enabled") == "true" {
 		protocol = "https"
 	}
-	_, err = connection.Write([]byte(fmt.Sprintf("Forwarding your traffic to %s://%s.%s \r\n", protocol, i.getSlug(), domain)))
+	_, err = connection.Write([]byte(fmt.Sprintf("Forwarding your traffic to %s://%s.%s \r\n", protocol, i.SlugManager.Get(), domain)))
 	if err != nil {
 		log.Printf("failed to write to channel: %v", err)
 		return
@@ -233,7 +256,7 @@ func (i *Interaction) HandleSlugSave(connection ssh.Channel) {
 	i.CommandBuffer.Reset()
 }
 
-func (i *Interaction) HandleSlugCancel(connection ssh.Channel, commandBuffer *bytes.Buffer) {
+func (i *Interaction) HandleSlugCancel(connection ssh.Channel) {
 	i.EditMode = false
 	_, err := connection.Write([]byte("\033[H\033[2J"))
 	if err != nil {
@@ -260,7 +283,7 @@ func (i *Interaction) HandleSlugCancel(connection ssh.Channel, commandBuffer *by
 	}
 	i.ShowWelcomeMessage()
 
-	commandBuffer.Reset()
+	i.CommandBuffer.Reset()
 }
 
 func (i *Interaction) HandleSlugUpdateError() {
@@ -271,44 +294,44 @@ func (i *Interaction) HandleSlugUpdateError() {
 		i.SendMessage(fmt.Sprintf("Disconnecting in %d...\r\n", iter))
 		time.Sleep(1 * time.Second)
 	}
-	err := i.session.Close()
+	err := i.Lifecycle.Close()
 	if err != nil {
 		log.Printf("failed to close session: %v", err)
 		return
 	}
 }
 
-func (i *Interaction) HandleCommand(command string, commandBuffer *bytes.Buffer) {
+func (i *Interaction) HandleCommand(command string) {
 	switch command {
 	case "/bye":
 		i.SendMessage("\r\nClosing connection...")
-		err := i.session.Close()
+		err := i.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 			return
 		}
 		return
 	case "/help":
-		i.SendMessage("\r\nAvailable commands: /bye, /help, /clear, /slug")
+		i.SendMessage("\r\nAvailable commands: /bye, /help, /clear, /slug\r\n")
 	case "/clear":
 		i.SendMessage("\033[H\033[2J")
 		i.ShowWelcomeMessage()
 		domain := utils.Getenv("domain")
-		if i.forwarder.GetTunnelType() == HTTP {
+		if i.Forwarder.GetTunnelType() == types.HTTP {
 			protocol := "http"
 			if utils.Getenv("tls_enabled") == "true" {
 				protocol = "https"
 			}
-			i.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s.%s \r\n", protocol, i.getSlug(), domain))
+			i.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s.%s \r\n", protocol, i.SlugManager.Get(), domain))
 		} else {
-			i.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s:%d \r\n", i.forwarder.GetTunnelType(), domain, i.forwarder.GetForwardedPort()))
+			i.SendMessage(fmt.Sprintf("Forwarding your traffic to %s://%s:%d \r\n", i.Forwarder.GetTunnelType(), domain, i.Forwarder.GetForwardedPort()))
 		}
 	case "/slug":
-		if i.forwarder.GetTunnelType() != HTTP {
-			i.SendMessage((fmt.Sprintf("\r\n%s tunnels cannot have custom subdomains", i.forwarder.GetTunnelType())))
+		if i.Forwarder.GetTunnelType() != types.HTTP {
+			i.SendMessage(fmt.Sprintf("\r\n%s tunnels cannot have custom subdomains", i.Forwarder.GetTunnelType()))
 		} else {
 			i.EditMode = true
-			i.EditSlug = i.getSlug()
+			i.EditSlug = i.SlugManager.Get()
 			i.SendMessage("\033[H\033[2J")
 			i.DisplaySlugEditor()
 			i.SendMessage("➤ " + i.EditSlug + "." + utils.Getenv("domain"))
@@ -317,7 +340,7 @@ func (i *Interaction) HandleCommand(command string, commandBuffer *bytes.Buffer)
 		i.SendMessage("Unknown command")
 	}
 
-	commandBuffer.Reset()
+	i.CommandBuffer.Reset()
 }
 
 func (i *Interaction) ShowWelcomeMessage() {
@@ -347,7 +370,7 @@ func (i *Interaction) ShowWelcomeMessage() {
 
 func (i *Interaction) DisplaySlugEditor() {
 	domain := utils.Getenv("domain")
-	fullDomain := i.getSlug() + "." + domain
+	fullDomain := i.SlugManager.Get() + "." + domain
 
 	const paddingRight = 4
 
@@ -383,23 +406,8 @@ func (i *Interaction) DisplaySlugEditor() {
 	i.SendMessage("\r\n\r\n")
 }
 
-func updateClientSlug(oldSlug, newSlug string) bool {
-	clientsMutex.Lock()
-	defer clientsMutex.Unlock()
-
-	if _, exists := Clients[newSlug]; exists && newSlug != oldSlug {
-		return false
-	}
-
-	client, ok := Clients[oldSlug]
-	if !ok {
-		return false
-	}
-
-	delete(Clients, oldSlug)
-	client.Forwarder.setSlug(newSlug)
-	Clients[newSlug] = client
-	return true
+func (i *Interaction) SetSlugModificator(modificator func(oldSlug, newSlug string) bool) {
+	i.updateClientSlug = modificator
 }
 
 func centerText(text string, width int) string {
@@ -409,3 +417,40 @@ func centerText(text string, width int) string {
 	}
 	return strings.Repeat(" ", padding) + text + strings.Repeat(" ", width-len(text)-padding)
 }
+
+func isValidSlug(slug string) bool {
+	if len(slug) < 3 || len(slug) > 20 {
+		return false
+	}
+
+	if slug[0] == '-' || slug[len(slug)-1] == '-' {
+		return false
+	}
+
+	for _, c := range slug {
+		if !((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '-') {
+			return false
+		}
+	}
+
+	return true
+}
+
+func waitForKeyPress(connection ssh.Channel) {
+	keyBuf := make([]byte, 1)
+	for {
+		_, err := connection.Read(keyBuf)
+		if err == nil {
+			break
+		}
+	}
+}
+
+func isForbiddenSlug(slug string) bool {
+	for _, s := range forbiddenSlug {
+		if slug == s {
+			return true
+		}
+	}
+	return false
+}

session/lifecycle/lifecycle.go

@@ -0,0 +1,126 @@
+package lifecycle
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"time"
+	portUtil "tunnel_pls/internal/port"
+	"tunnel_pls/session/slug"
+	"tunnel_pls/types"
+
+	"golang.org/x/crypto/ssh"
+)
+
+type Interaction interface {
+	SendMessage(string)
+}
+
+type Forwarder interface {
+	Close() error
+	GetTunnelType() types.TunnelType
+	GetForwardedPort() uint16
+}
+
+type Lifecycle struct {
+	Status  types.Status
+	Conn    ssh.Conn
+	Channel ssh.Channel
+
+	Interaction      Interaction
+	Forwarder        Forwarder
+	SlugManager      slug.Manager
+	unregisterClient func(slug string)
+}
+
+func (l *Lifecycle) SetUnregisterClient(unregisterClient func(slug string)) {
+	l.unregisterClient = unregisterClient
+}
+
+type SessionLifecycle interface {
+	Close() error
+	WaitForRunningStatus()
+	SetStatus(status types.Status)
+	GetConnection() ssh.Conn
+	GetChannel() ssh.Channel
+	SetChannel(channel ssh.Channel)
+	SetUnregisterClient(unregisterClient func(slug string))
+}
+
+func (l *Lifecycle) GetChannel() ssh.Channel {
+	return l.Channel
+}
+
+func (l *Lifecycle) SetChannel(channel ssh.Channel) {
+	l.Channel = channel
+}
+func (l *Lifecycle) GetConnection() ssh.Conn {
+	return l.Conn
+}
+func (l *Lifecycle) SetStatus(status types.Status) {
+	l.Status = status
+}
+func (l *Lifecycle) WaitForRunningStatus() {
+	timeout := time.After(3 * time.Second)
+	ticker := time.NewTicker(150 * time.Millisecond)
+	defer ticker.Stop()
+	frames := []string{"-", "\\", "|", "/"}
+	i := 0
+	for {
+		select {
+		case <-ticker.C:
+			l.Interaction.SendMessage(fmt.Sprintf("\rLoading %s", frames[i]))
+			i = (i + 1) % len(frames)
+			if l.Status == types.RUNNING {
+				l.Interaction.SendMessage("\r\033[K")
+				return
+			}
+		case <-timeout:
+			l.Interaction.SendMessage("\r\033[K")
+			l.Interaction.SendMessage("TCP/IP request not received in time.\r\nCheck your internet connection and confirm the server responds within 3000ms.\r\nEnsure you ran the correct command. For more details, visit https://tunnl.live.\r\n\r\n")
+			err := l.Close()
+			if err != nil {
+				log.Printf("failed to close session: %v", err)
+			}
+			log.Println("Timeout waiting for session to start running")
+			return
+		}
+	}
+}
+
+func (l *Lifecycle) Close() error {
+	err := l.Forwarder.Close()
+	if err != nil && !errors.Is(err, net.ErrClosed) {
+		return err
+	}
+
+	if l.Channel != nil {
+		err := l.Channel.Close()
+		if err != nil && !errors.Is(err, io.EOF) {
+			return err
+		}
+	}
+
+	if l.Conn != nil {
+		err := l.Conn.Close()
+		if err != nil && !errors.Is(err, net.ErrClosed) {
+			return err
+		}
+	}
+
+	clientSlug := l.SlugManager.Get()
+	if clientSlug != "" {
+		l.unregisterClient(clientSlug)
+	}
+
+	if l.Forwarder.GetTunnelType() == types.TCP {
+		err := portUtil.Manager.SetPortStatus(l.Forwarder.GetForwardedPort(), false)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

session/session.go

@@ -4,102 +4,85 @@ import (
 	"bytes"
 	"log"
 	"sync"
+	"tunnel_pls/session/forwarder"
+	"tunnel_pls/session/interaction"
+	"tunnel_pls/session/lifecycle"
+	"tunnel_pls/session/slug"
+	"tunnel_pls/types"
 
 	"golang.org/x/crypto/ssh"
 )
 
-const (
-	INITIALIZING Status = "INITIALIZING"
-	RUNNING      Status = "RUNNING"
-	SETUP        Status = "SETUP"
+var (
+	clientsMutex sync.RWMutex
+	Clients      = make(map[string]*SSHSession)
 )
 
-type TunnelType string
-
-const (
-	HTTP TunnelType = "http"
-	TCP  TunnelType = "tcp"
-)
-
-type SessionLifecycle interface {
-	Close() error
-	WaitForRunningStatus()
-}
-
-type SessionCloser interface {
-	Close() error
-}
-
 type Session interface {
-	SessionLifecycle
-	InteractionController
-	ForwardingController
-}
-
-type Lifecycle struct {
-	Status Status
+	HandleGlobalRequest(ch <-chan *ssh.Request)
+	HandleTCPIPForward(req *ssh.Request)
+	HandleHTTPForward(req *ssh.Request, port uint16)
+	HandleTCPForward(req *ssh.Request, addr string, port uint16)
 }
 
 type SSHSession struct {
-	Lifecycle   *Lifecycle
-	Interaction *Interaction
-	Forwarder   *Forwarder
-
-	Conn    *ssh.ServerConn
-	channel ssh.Channel
-
-	slug   string
-	slugMu sync.RWMutex
+	Lifecycle   lifecycle.SessionLifecycle
+	Interaction interaction.Controller
+	Forwarder   forwarder.ForwardingController
+	SlugManager slug.Manager
 }
 
 func New(conn *ssh.ServerConn, forwardingReq <-chan *ssh.Request, sshChan <-chan ssh.NewChannel) {
-	session := SSHSession{
-		Lifecycle: &Lifecycle{
-			Status: INITIALIZING,
-		},
-		Interaction: &Interaction{
-			CommandBuffer: new(bytes.Buffer),
-			EditMode:      false,
-			EditSlug:      "",
-			channel:       nil,
-			getSlug:       nil,
-			setSlug:       nil,
-			session:       nil,
-			forwarder:     nil,
-		},
-		Forwarder: &Forwarder{
+	slugManager := slug.NewManager()
+	forwarderManager := &forwarder.Forwarder{
 		Listener:      nil,
 		TunnelType:    "",
 		ForwardedPort: 0,
-			getSlug:       nil,
-			setSlug:       nil,
-		},
+		SlugManager:   slugManager,
+	}
+	interactionManager := &interaction.Interaction{
+		CommandBuffer: bytes.NewBuffer(make([]byte, 0, 20)),
+		EditMode:      false,
+		EditSlug:      "",
+		SlugManager:   slugManager,
+		Forwarder:     forwarderManager,
+		Lifecycle:     nil,
+	}
+	lifecycleManager := &lifecycle.Lifecycle{
+		Status:      "",
 		Conn:        conn,
-		channel: nil,
-		slug:    "",
+		Channel:     nil,
+		Interaction: interactionManager,
+		Forwarder:   forwarderManager,
+		SlugManager: slugManager,
 	}
 
-	session.Forwarder.getSlug = session.GetSlug
-	session.Forwarder.setSlug = session.SetSlug
-	session.Interaction.getSlug = session.GetSlug
-	session.Interaction.setSlug = session.SetSlug
-	session.Interaction.session = &session
-	session.Interaction.forwarder = session.Forwarder
+	interactionManager.SetLifecycle(lifecycleManager)
+	interactionManager.SetSlugModificator(updateClientSlug)
+	forwarderManager.SetLifecycle(lifecycleManager)
+	lifecycleManager.SetUnregisterClient(unregisterClient)
+	
+	session := &SSHSession{
+		Lifecycle:   lifecycleManager,
+		Interaction: interactionManager,
+		Forwarder:   forwarderManager,
+		SlugManager: slugManager,
+	}
 
 	go func() {
-		go session.waitForRunningStatus()
+		go session.Lifecycle.WaitForRunningStatus()
 
 		for channel := range sshChan {
 			ch, reqs, _ := channel.Accept()
-			if session.channel == nil {
-				session.channel = ch
-				session.Interaction.channel = ch
-				session.Lifecycle.Status = SETUP
+			if session.Lifecycle.GetChannel() == nil {
+				session.Lifecycle.SetChannel(ch)
+				session.Interaction.SetChannel(ch)
+				session.Lifecycle.SetStatus(types.SETUP)
 				go session.HandleGlobalRequest(forwardingReq)
 			}
 			go session.HandleGlobalRequest(reqs)
 		}
-		err := session.Close()
+		err := session.Lifecycle.Close()
 		if err != nil {
 			log.Printf("failed to close session: %v", err)
 		}
@@ -107,14 +90,40 @@ func New(conn *ssh.ServerConn, forwardingReq <-chan *ssh.Request, sshChan <-chan
 	}()
 }
 
-func (s *SSHSession) GetSlug() string {
-	s.slugMu.RLock()
-	defer s.slugMu.RUnlock()
-	return s.slug
+func updateClientSlug(oldSlug, newSlug string) bool {
+	clientsMutex.Lock()
+	defer clientsMutex.Unlock()
+
+	if _, exists := Clients[newSlug]; exists && newSlug != oldSlug {
+		return false
+	}
+
+	client, ok := Clients[oldSlug]
+	if !ok {
+		return false
+	}
+
+	delete(Clients, oldSlug)
+	client.SlugManager.Set(newSlug)
+	Clients[newSlug] = client
+	return true
 }
 
-func (s *SSHSession) SetSlug(slug string) {
-	s.slugMu.Lock()
-	s.slug = slug
-	s.slugMu.Unlock()
+func registerClient(slug string, session *SSHSession) bool {
+	clientsMutex.Lock()
+	defer clientsMutex.Unlock()
+
+	if _, exists := Clients[slug]; exists {
+		return false
+	}
+
+	Clients[slug] = session
+	return true
+}
+
+func unregisterClient(slug string) {
+	clientsMutex.Lock()
+	defer clientsMutex.Unlock()
+
+	delete(Clients, slug)
 }

session/slug/slug.go

@@ -0,0 +1,32 @@
+package slug
+
+import "sync"
+
+type Manager interface {
+	Get() string
+	Set(slug string)
+}
+
+type manager struct {
+	slug   string
+	slugMu sync.RWMutex
+}
+
+func NewManager() Manager {
+	return &manager{
+		slug:   "",
+		slugMu: sync.RWMutex{},
+	}
+}
+
+func (s *manager) Get() string {
+	s.slugMu.RLock()
+	defer s.slugMu.RUnlock()
+	return s.slug
+}
+
+func (s *manager) Set(slug string) {
+	s.slugMu.Lock()
+	s.slug = slug
+	s.slugMu.Unlock()
+}

types/types.go

@@ -0,0 +1,16 @@
+package types
+
+type Status string
+
+const (
+	INITIALIZING Status = "INITIALIZING"
+	RUNNING      Status = "RUNNING"
+	SETUP        Status = "SETUP"
+)
+
+type TunnelType string
+
+const (
+	HTTP TunnelType = "HTTP"
+	TCP  TunnelType = "TCP"
+)