Generic Listener supporting unencrypted, encrypted, with TLS version detection before TLS Accept

- added support for context passing between the various functions
- support for withCancel, allowing administrative canceling, and a clean up of Go Routines.
- generic listener now supports a single port for both encrypted and clear text protocols.
- employee the buffered wedge connection for peaking into the protocol
- implementation of the oneListener.
- when TLS, leveraged the NewListener which uses oneListener as n inner lister.
- once the stream is decrypted, or if it was already clear text it is passed to handleStream which performs application detection.

rvpn/connection/connection_table.go

@@ -2,6 +2,7 @@ package connection
 
 import "fmt"
 import "time"
+import "context"
 
 const (
 	initialDomains   = 0
@@ -62,13 +63,18 @@ func (c *Table) reaper(delay int, idle int) {
 }
 
 //Run -- Execute
-func (c *Table) Run() {
+func (c *Table) Run(ctx context.Context) {
 	loginfo.Println("ConnectionTable starting")
 
 	go c.reaper(300, 60)
 
 	for {
 		select {
+
+		case <-ctx.Done():
+			loginfo.Println("Cancel signal hit")
+			return
+
 		case registration := <-c.register:
 			loginfo.Println("register fired")
 

rvpn/genericlistener/listener_generic.go

@@ -1,67 +1,148 @@
 package genericlistener
 
 import (
-	"net"
-
+	"bytes"
+	"context"
 	"crypto/tls"
+	"encoding/hex"
+	"log"
+	"net"
+	"time"
 
 	"git.daplie.com/Daplie/go-rvpn-server/rvpn/connection"
 )
 
-//LaunchGenericServer -- used to lisen for any https traffic on 443 (8443)
-//used to make sure customer devices can reach 443. wss or client
-func LaunchGenericServer(connectionTable *connection.Table, secretKey string, serverBinding string, certbundle tls.Certificate) {
-
-	config := &tls.Config{Certificates: []tls.Certificate{certbundle}}
-
-	listener, err := tls.Listen("tcp", serverBinding, config)
-	if err != nil {
-		loginfo.Println("unable to bind ", serverBinding)
-		return
-	}
-
-	defer listener.Close()
-
-	for {
-		conn, err := listener.Accept()
-		if err != nil {
-			loginfo.Println("Bad accept ", err)
-			continue
-		}
-
-		go handleConnection(conn, connectionTable, secretKey)
-	}
-}
-
-type protocol int
-
-//Family -- ENUM for Address Family
 const (
-	protoHTTP protocol = iota + 1
-	protoHTTPS
-	protoSSLV3
-	protoTLSV1
-	protoTLSV11
-	protoTLSV2
+	encryptNone int = iota
+	encryptSSLV2
+	encryptSSLV3
+	encryptTLS10
+	encryptTLS11
+	encryptTLS12
 )
 
-//State -- state of connection
-type State struct {
-	Protocol protocol
-}
+//GenericListenAndServe -- used to lisen for any https traffic on 443 (8443)
+// - setup generic TCP listener, unencrypted TCP, with a Deadtime out
+// - leaverage the wedgeConn to peek into the buffer.
+// - if TLS, consume connection with TLS certbundle, pass to request identifier
+// - else, just pass to the request identififer
+func GenericListenAndServe(ctx context.Context, connectionTable *connection.Table, secretKey string, serverBinding string, certbundle tls.Certificate, deadTime int) {
+	config := &tls.Config{Certificates: []tls.Certificate{certbundle}}
 
-//NewState -- Constructor
-func NewState() (p *State) {
-	p = new(State)
+	listenAddr, err := net.ResolveTCPAddr("tcp", serverBinding)
+	if nil != err {
+		loginfo.Println(err)
 		return
 	}
 
-func handleConnection(conn net.Conn, connectionTable *connection.Table, secretKey string) {
-	defer conn.Close()
+	ln, err := net.ListenTCP("tcp", listenAddr)
+	if err != nil {
+		loginfo.Println("unable to bind", err)
+		return
+	}
 
-	loginfo.Println("conn", conn)
-	loginfo.Println("hank")
-	loginfo.Println("here", conn.LocalAddr().String(), conn.RemoteAddr().String())
+	for {
+		select {
+		case <-ctx.Done():
+			loginfo.Println("Cancel signal hit")
+			return
+		default:
+			ln.SetDeadline(time.Now().Add(time.Duration(deadTime) * time.Second))
+
+			conn, err := ln.Accept()
+
+			loginfo.Println("Deadtime reached")
+
+			if nil != err {
+				if opErr, ok := err.(*net.OpError); ok && opErr.Timeout() {
+					continue
+				}
+				log.Println(err)
+				return
+			}
+
+			wedgeConn := NewWedgeConn(conn)
+			go handleConnection(ctx, wedgeConn, connectionTable, secretKey, config)
+		}
+	}
+}
+
+//handleConnection -
+// - accept a wedgeConnection along with all the other required attritvues
+// - peek into the buffer, determine TLS or unencrypted
+
+func handleConnection(ctx context.Context, wConn *WedgeConn, connectionTable *connection.Table, secretKey string, config *tls.Config) {
+	defer wConn.Close()
+	peekCnt := 10
+
+	encryptMode := encryptNone
+
+	loginfo.Println("conn", wConn, wConn.LocalAddr().String(), wConn.RemoteAddr().String())
+	peek, err := wConn.Peek(peekCnt)
+
+	if err != nil {
+		loginfo.Println("error while peeking")
+		return
+	}
+	loginfo.Println(hex.Dump(peek[0:peekCnt]))
+	loginfo.Println(hex.Dump(peek[2:4]))
+	loginfo.Println("after peek")
+
+	//take a look for a TLS header.
+	if bytes.Contains(peek[0:0], []byte{0x80}) && bytes.Contains(peek[2:4], []byte{0x01, 0x03}) {
+		encryptMode = encryptSSLV2
+
+	} else if bytes.Contains(peek[0:3], []byte{0x16, 0x03, 0x00}) {
+		encryptMode = encryptSSLV3
+
+	} else if bytes.Contains(peek[0:3], []byte{0x16, 0x03, 0x01}) {
+		encryptMode = encryptTLS10
+		loginfo.Println("TLS10")
+
+	} else if bytes.Contains(peek[0:3], []byte{0x16, 0x03, 0x02}) {
+		encryptMode = encryptTLS11
+
+	} else if bytes.Contains(peek[0:3], []byte{0x16, 0x03, 0x03}) {
+		encryptMode = encryptTLS12
+	}
+
+	oneConn := &oneConnListener{wConn}
+
+	if encryptMode == encryptSSLV2 {
+		loginfo.Println("SSLv2 is not accepted")
+		return
+
+	} else if encryptMode != encryptNone {
+		loginfo.Println("Handle Encryption")
+		tlsListener := tls.NewListener(oneConn, config)
+
+		conn, err := tlsListener.Accept()
+		if err != nil {
+			loginfo.Println(err)
+			return
+		}
+		loginfo.Println(conn)
+		handleStream(conn)
+		return
+	}
+
+	loginfo.Println("Handle Unencrypted")
+	handleStream(wConn)
+
+	return
+}
+
+func handleStream(conn net.Conn) {
+	var buf [512]byte
+	cnt, err := conn.Read(buf[0:])
+	if err != nil {
+		loginfo.Println(err)
+		return
+	}
+
+	loginfo.Println(hex.Dump(buf[0:cnt]))
+
+}
 
 //state := NewState()
 //wConn := NewWedgeConnSize(conn, 512)
@@ -84,6 +165,3 @@ func handleConnection(conn net.Conn, connectionTable *connection.Table, secretKe
 
 //wedgeListener := &WedgeListener{conn: conn}
 //LaunchWssListener(connectionTable, &secretKey, wedgeListener)
-
-	return
-}

rvpn/genericlistener/listener_wedge.go

@@ -9,6 +9,7 @@ import (
 
 //WedgeListener -- used to hand off connections to other protocols via Listen
 type WedgeListener struct {
+	net.Listener
 	conn net.Conn
 	once sync.Once
 }

rvpn/genericlistener/one_conn.go

@@ -0,0 +1,34 @@
+package genericlistener
+
+import (
+	"io"
+	"net"
+)
+
+type oneConnListener struct {
+	conn net.Conn
+}
+
+func (l *oneConnListener) Accept() (c net.Conn, err error) {
+	c = l.conn
+
+	if c == nil {
+		err = io.EOF
+		loginfo.Println("Accept")
+		return
+	}
+	err = nil
+	l.conn = nil
+	loginfo.Println("Accept", c.LocalAddr().String(), c.RemoteAddr().String())
+	return
+}
+
+func (l *oneConnListener) Close() error {
+	loginfo.Println("close")
+	return nil
+}
+
+func (l *oneConnListener) Addr() net.Addr {
+	loginfo.Println("addr")
+	return nil
+}

rvpn/rvpnmain/run.go

@@ -1,10 +1,14 @@
 package rvpnmain
 
 import (
+	"crypto/tls"
 	"flag"
 	"fmt"
 	"log"
 	"os"
+	"time"
+
+	"context"
 
 	"git.daplie.com/Daplie/go-rvpn-server/rvpn/connection"
 	"git.daplie.com/Daplie/go-rvpn-server/rvpn/genericlistener"
@@ -20,17 +24,18 @@ var (
 	argServerBinding         string
 	argServerAdminBinding    string
 	argServerExternalBinding string
+	argDeadTime              int
 	connectionTable          *connection.Table
 	wssMapping               *xlate.WssMapping
 	secretKey                = "abc123"
 )
 
 func init() {
-	flag.StringVar(&argGenericBinding, "ssl-listener", ":8443", "generic SSL Listener")
+	flag.IntVar(&argDeadTime, "dead-time-counter", 5, "deadtime counter in seconds")
+	flag.StringVar(&argGenericBinding, "generic-listener", ":8443", "generic SSL Listener")
 	flag.StringVar(&argWssClientListener, "wss-client-listener", ":3502", "wss client listener address:port")
 	flag.StringVar(&argServerAdminBinding, "admin-server-port", "127.0.0.2:8000", "admin server Bind listener")
 	flag.StringVar(&argServerExternalBinding, "external-server-port", "127.0.0.1:8080", "external server Bind listener")
-
 }
 
 //Run -- main entry point
@@ -44,18 +49,35 @@ func Run() {
 
 	fmt.Println("-=-=-=-=-=-=-=-=-=-=")
 
-	// certbundle, err := tls.LoadX509KeyPair("certs/fullchain.pem", "certs/privkey.pem")
-	// if err != nil {
-	// 	loginfo.Println(err)
-	// 	return
-	// }
-	// loginfo.Println(certbundle)
+	certbundle, err := tls.LoadX509KeyPair("certs/fullchain.pem", "certs/privkey.pem")
+	if err != nil {
+		loginfo.Println(err)
+		return
+	}
 
-	wssMapping = xlate.NewwssMapping()
-	go wssMapping.Run()
+	ctx, cancelContext := context.WithCancel(context.Background())
+	defer cancelContext()
 
 	connectionTable = connection.NewTable()
-	go connectionTable.Run()
+	go connectionTable.Run(ctx)
+
+	// Setup for GenericListenServe.
+	// - establish context for the generic listener
+	// - startup listener
+	// - accept with peek buffer.
+	// - peek at the 1st 30 bytes.
+	// - check for tls
+	// - if tls, establish, protocol peek buffer, else decrypted
+	// - match protocol
+
+	go genericlistener.GenericListenAndServe(ctx, connectionTable, secretKey, argGenericBinding, certbundle, argDeadTime)
+
+	time.Sleep(300 * time.Second)
+	cancelContext()
+	time.Sleep(60 * time.Second)
+
+	//wssMapping = xlate.NewwssMapping()
+	//go wssMapping.Run()
 
 	//go client.LaunchClientListener(connectionTable, &secretKey, &argServerBinding)
 	//go external.LaunchWebRequestExternalListener(&argServerExternalBinding, connectionTable)
@@ -65,5 +87,5 @@ func Run() {
 	//	loginfo.Println("LauchAdminListener failed: ", err)
 	//}
 
-	genericlistener.LaunchWssListener(connectionTable, secretKey, argWssClientListener, "certs/fullchain.pem", "certs/privkey.pem")
+	//genericlistener.LaunchWssListener(connectionTable, secretKey, argWssClientListener, "certs/fullchain.pem", "certs/privkey.pem")
 }