Refactoring main into separate modules

1 files changed, 91 insertions, 263 deletions

diff --git a/obfs4proxy/obfs4proxy.go b/obfs4proxy/obfs4proxy.go
index f66f7c0..92a34c0 100644
--- a/obfs4proxy/obfs4proxy.go
+++ b/obfs4proxy/obfs4proxy.go
@@ -32,22 +32,21 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io"
 	golog "log"
 	"net"
-	"net/url"
 	"os"
 	"path"
-	"sync"
 	"syscall"
 
-	"golang.org/x/net/proxy"
-
 	"git.torproject.org/pluggable-transports/goptlib.git"
-	"git.torproject.org/pluggable-transports/obfs4.git/common/log"
-	"git.torproject.org/pluggable-transports/obfs4.git/common/socks5"
-	"git.torproject.org/pluggable-transports/obfs4.git/transports"
-	"git.torproject.org/pluggable-transports/obfs4.git/transports/base"
+	"github.com/OperatorFoundation/obfs4/common/log"
+	"github.com/OperatorFoundation/obfs4/common/termmon"
+	"github.com/OperatorFoundation/obfs4/common/pt_extras"
+	"github.com/OperatorFoundation/obfs4/transports"
+
+	"github.com/OperatorFoundation/obfs4/proxies/proxy_socks5"
+	"github.com/OperatorFoundation/obfs4/proxies/proxy_transparent"
+	"github.com/OperatorFoundation/obfs4/proxies/proxy_transparent_udp"
 )
 
 const (
@@ -57,249 +56,7 @@ const (
 )
 
 var stateDir string
-var termMon *termMonitor
-
-func clientSetup() (launched bool, listeners []net.Listener) {
-	ptClientInfo, err := pt.ClientSetup(transports.Transports())
-	if err != nil {
-		golog.Fatal(err)
-	}
-
-	ptClientProxy, err := ptGetProxy()
-	if err != nil {
-		golog.Fatal(err)
-	} else if ptClientProxy != nil {
-		ptProxyDone()
-	}
-
-	// Launch each of the client listeners.
-	for _, name := range ptClientInfo.MethodNames {
-		t := transports.Get(name)
-		if t == nil {
-			pt.CmethodError(name, "no such transport is supported")
-			continue
-		}
-
-		f, err := t.ClientFactory(stateDir)
-		if err != nil {
-			pt.CmethodError(name, "failed to get ClientFactory")
-			continue
-		}
-
-		ln, err := net.Listen("tcp", socksAddr)
-		if err != nil {
-			pt.CmethodError(name, err.Error())
-			continue
-		}
-
-		go clientAcceptLoop(f, ln, ptClientProxy)
-		pt.Cmethod(name, socks5.Version(), ln.Addr())
-
-		log.Infof("%s - registered listener: %s", name, ln.Addr())
-
-		listeners = append(listeners, ln)
-		launched = true
-	}
-	pt.CmethodsDone()
-
-	return
-}
-
-func clientAcceptLoop(f base.ClientFactory, ln net.Listener, proxyURI *url.URL) error {
-	defer ln.Close()
-	for {
-		conn, err := ln.Accept()
-		if err != nil {
-			if e, ok := err.(net.Error); ok && !e.Temporary() {
-				return err
-			}
-			continue
-		}
-		go clientHandler(f, conn, proxyURI)
-	}
-}
-
-func clientHandler(f base.ClientFactory, conn net.Conn, proxyURI *url.URL) {
-	defer conn.Close()
-	termMon.onHandlerStart()
-	defer termMon.onHandlerFinish()
-
-	name := f.Transport().Name()
-
-	// Read the client's SOCKS handshake.
-	socksReq, err := socks5.Handshake(conn)
-	if err != nil {
-		log.Errorf("%s - client failed socks handshake: %s", name, err)
-		return
-	}
-	addrStr := log.ElideAddr(socksReq.Target)
-
-	// Deal with arguments.
-	args, err := f.ParseArgs(&socksReq.Args)
-	if err != nil {
-		log.Errorf("%s(%s) - invalid arguments: %s", name, addrStr, err)
-		socksReq.Reply(socks5.ReplyGeneralFailure)
-		return
-	}
-
-	// Obtain the proxy dialer if any, and create the outgoing TCP connection.
-	dialFn := proxy.Direct.Dial
-	if proxyURI != nil {
-		dialer, err := proxy.FromURL(proxyURI, proxy.Direct)
-		if err != nil {
-			// This should basically never happen, since config protocol
-			// verifies this.
-			log.Errorf("%s(%s) - failed to obtain proxy dialer: %s", name, addrStr, log.ElideError(err))
-			socksReq.Reply(socks5.ReplyGeneralFailure)
-			return
-		}
-		dialFn = dialer.Dial
-	}
-	remote, err := f.Dial("tcp", socksReq.Target, dialFn, args)
-	if err != nil {
-		log.Errorf("%s(%s) - outgoing connection failed: %s", name, addrStr, log.ElideError(err))
-		socksReq.Reply(socks5.ErrorToReplyCode(err))
-		return
-	}
-	defer remote.Close()
-	err = socksReq.Reply(socks5.ReplySucceeded)
-	if err != nil {
-		log.Errorf("%s(%s) - SOCKS reply failed: %s", name, addrStr, log.ElideError(err))
-		return
-	}
-
-	if err = copyLoop(conn, remote); err != nil {
-		log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err))
-	} else {
-		log.Infof("%s(%s) - closed connection", name, addrStr)
-	}
-
-	return
-}
-
-func serverSetup() (launched bool, listeners []net.Listener) {
-	ptServerInfo, err := pt.ServerSetup(transports.Transports())
-	if err != nil {
-		golog.Fatal(err)
-	}
-
-	for _, bindaddr := range ptServerInfo.Bindaddrs {
-		name := bindaddr.MethodName
-		t := transports.Get(name)
-		if t == nil {
-			pt.SmethodError(name, "no such transport is supported")
-			continue
-		}
-
-		f, err := t.ServerFactory(stateDir, &bindaddr.Options)
-		if err != nil {
-			pt.SmethodError(name, err.Error())
-			continue
-		}
-
-		ln, err := net.ListenTCP("tcp", bindaddr.Addr)
-		if err != nil {
-			pt.SmethodError(name, err.Error())
-			continue
-		}
-
-		go serverAcceptLoop(f, ln, &ptServerInfo)
-		if args := f.Args(); args != nil {
-			pt.SmethodArgs(name, ln.Addr(), *args)
-		} else {
-			pt.SmethodArgs(name, ln.Addr(), nil)
-		}
-
-		log.Infof("%s - registered listener: %s", name, log.ElideAddr(ln.Addr().String()))
-
-		listeners = append(listeners, ln)
-		launched = true
-	}
-	pt.SmethodsDone()
-
-	return
-}
-
-func serverAcceptLoop(f base.ServerFactory, ln net.Listener, info *pt.ServerInfo) error {
-	defer ln.Close()
-	for {
-		conn, err := ln.Accept()
-		if err != nil {
-			if e, ok := err.(net.Error); ok && !e.Temporary() {
-				return err
-			}
-			continue
-		}
-		go serverHandler(f, conn, info)
-	}
-}
-
-func serverHandler(f base.ServerFactory, conn net.Conn, info *pt.ServerInfo) {
-	defer conn.Close()
-	termMon.onHandlerStart()
-	defer termMon.onHandlerFinish()
-
-	name := f.Transport().Name()
-	addrStr := log.ElideAddr(conn.RemoteAddr().String())
-	log.Infof("%s(%s) - new connection", name, addrStr)
-
-	// Instantiate the server transport method and handshake.
-	remote, err := f.WrapConn(conn)
-	if err != nil {
-		log.Warnf("%s(%s) - handshake failed: %s", name, addrStr, log.ElideError(err))
-		return
-	}
-
-	// Connect to the orport.
-	orConn, err := pt.DialOr(info, conn.RemoteAddr().String(), name)
-	if err != nil {
-		log.Errorf("%s(%s) - failed to connect to ORPort: %s", name, addrStr, log.ElideError(err))
-		return
-	}
-	defer orConn.Close()
-
-	if err = copyLoop(orConn, remote); err != nil {
-		log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err))
-	} else {
-		log.Infof("%s(%s) - closed connection", name, addrStr)
-	}
-
-	return
-}
-
-func copyLoop(a net.Conn, b net.Conn) error {
-	// Note: b is always the pt connection.  a is the SOCKS/ORPort connection.
-	errChan := make(chan error, 2)
-
-	var wg sync.WaitGroup
-	wg.Add(2)
-
-	go func() {
-		defer wg.Done()
-		defer b.Close()
-		defer a.Close()
-		_, err := io.Copy(b, a)
-		errChan <- err
-	}()
-	go func() {
-		defer wg.Done()
-		defer a.Close()
-		defer b.Close()
-		_, err := io.Copy(a, b)
-		errChan <- err
-	}()
-
-	// Wait for both upstream and downstream to close.  Since one side
-	// terminating closes the other, the second error in the channel will be
-	// something like EINVAL (though io.Copy() will swallow EOF), so only the
-	// first error is returned.
-	wg.Wait()
-	if len(errChan) > 0 {
-		return <-errChan
-	}
-
-	return nil
-}
+var termMon *termmon.TermMonitor
 
 func getVersion() string {
 	return fmt.Sprintf("obfs4proxy-%s", obfs4proxyVersion)
@@ -307,7 +64,7 @@ func getVersion() string {
 
 func main() {
 	// Initialize the termination state monitor as soon as possible.
-	termMon = newTermMonitor()
+	termMon = termmon.NewTermMonitor()
 
 	// Handle the command line arguments.
 	_, execName := path.Split(os.Args[0])
@@ -315,6 +72,13 @@ func main() {
 	logLevelStr := flag.String("logLevel", "ERROR", "Log level (ERROR/WARN/INFO/DEBUG)")
 	enableLogging := flag.Bool("enableLogging", false, "Log to TOR_PT_STATE_LOCATION/"+obfs4proxyLogFile)
 	unsafeLogging := flag.Bool("unsafeLogging", false, "Disable the address scrubber")
+	transparent := flag.Bool("transparent", false, "Enable transparent proxy mode")
+	udp := flag.Bool("udp", false, "Enable UDP proxy mode")
+	target := flag.String("target", "", "Specify transport server destination address")
+	clientMode := flag.Bool("client", false, "Enable client mode")
+	serverMode := flag.Bool("server", false, "Enable server mode")
+	statePath := flag.String("state", "", "Specify transport server destination address")
+	bindAddr := flag.String("bindaddr", "", "Specify the bind address for transparent server")
 	flag.Parse()
 
 	if *showVer {
@@ -328,11 +92,11 @@ func main() {
 	// Determine if this is a client or server, initialize the common state.
 	var ptListeners []net.Listener
 	launched := false
-	isClient, err := ptIsClient()
+	isClient, err := checkIsClient(*clientMode, *serverMode)
 	if err != nil {
 		golog.Fatalf("[ERROR]: %s - must be run as a managed transport", execName)
 	}
-	if stateDir, err = pt.MakeStateDir(); err != nil {
+	if stateDir, err = makeStateDir(*statePath); err != nil {
 		golog.Fatalf("[ERROR]: %s - No state directory: %s", execName, err)
 	}
 	if err = log.Init(*enableLogging, path.Join(stateDir, obfs4proxyLogFile), *unsafeLogging); err != nil {
@@ -345,14 +109,58 @@ func main() {
 
 	log.Noticef("%s - launched", getVersion())
 
-	// Do the managed pluggable transport protocol configuration.
-	if isClient {
-		log.Infof("%s - initializing client transport listeners", execName)
-		launched, ptListeners = clientSetup()
+  if *transparent {
+		// Do the transparent proxy configuration.
+		log.Infof("%s - initializing transparent proxy", execName)
+		if *udp {
+			log.Infof("%s - initializing UDP transparent proxy", execName)
+			if isClient {
+				log.Infof("%s - initializing client transport listeners", execName)
+				if *target == "" {
+					log.Errorf("%s - transparent mode requires a target", execName)
+				} else {
+					launched = proxy_transparent_udp.ClientSetup(termMon, *target)
+				}
+			} else {
+				log.Infof("%s - initializing server transport listeners", execName)
+				if *bindAddr == "" {
+					fmt.Println("%s - transparent mode requires a bindaddr", execName)
+				} else {
+					launched = proxy_transparent_udp.ServerSetup(termMon, *bindAddr)
+					fmt.Println("launched", launched, ptListeners)
+				}
+			}
+		} else {
+			log.Infof("%s - initializing TCP transparent proxy", execName)
+			if isClient {
+				log.Infof("%s - initializing client transport listeners", execName)
+				if *target == "" {
+					log.Errorf("%s - transparent mode requires a target", execName)
+				} else {
+					launched, ptListeners = proxy_transparent.ClientSetup(termMon, *target)
+				}
+			} else {
+				log.Infof("%s - initializing server transport listeners", execName)
+				if *bindAddr == "" {
+					fmt.Println("%s - transparent mode requires a bindaddr", execName)
+				} else {
+					launched, ptListeners = proxy_transparent.ServerSetup(termMon, *bindAddr)
+					fmt.Println("launched", launched, ptListeners)
+				}
+			}
+		}
 	} else {
-		log.Infof("%s - initializing server transport listeners", execName)
-		launched, ptListeners = serverSetup()
+		// Do the managed pluggable transport protocol configuration.
+		log.Infof("%s - initializing PT 1.0 proxy", execName)
+		if isClient {
+			log.Infof("%s - initializing client transport listeners", execName)
+			launched, ptListeners = proxy_socks5.ClientSetup(termMon)
+		} else {
+			log.Infof("%s - initializing server transport listeners", execName)
+			launched, ptListeners = proxy_socks5.ServerSetup(termMon)
+		}
 	}
+
 	if !launched {
 		// Initialization failed, the client or server setup routines should
 		// have logged, so just exit here.
@@ -368,7 +176,7 @@ func main() {
 	// connections will be processed.  Wait till the parent dies
 	// (immediate exit), a SIGTERM is received (immediate exit),
 	// or a SIGINT is received.
-	if sig := termMon.wait(false); sig == syscall.SIGTERM {
+	if sig := termMon.Wait(false); sig == syscall.SIGTERM {
 		return
 	}
 
@@ -378,5 +186,25 @@ func main() {
 	for _, ln := range ptListeners {
 		ln.Close()
 	}
-	termMon.wait(true)
+
+	termMon.Wait(true)
+}
+
+func checkIsClient(client bool, server bool) (bool, error) {
+	if client {
+		return true, nil
+	} else if server {
+		return false, nil
+	} else {
+		return pt_extras.PtIsClient()
+	}
+}
+
+func makeStateDir(statePath string) (string, error) {
+	if statePath != "" {
+		err := os.MkdirAll(statePath, 0700)
+		return statePath, err
+	} else {
+		return pt.MakeStateDir()
+	}
 }