merge client stdio support (closes jpillora#166 thanks @BoleynSu!)

Author: jpillora

README.md

@@ -19,6 +19,7 @@ Chisel is a fast TCP tunnel, transported over HTTP, secured via SSH. Single exec
 - Server optionally doubles as a [reverse proxy](http://golang.org/pkg/net/http/httputil/#NewSingleHostReverseProxy)
 - Server optionally allows [SOCKS5](https://en.wikipedia.org/wiki/SOCKS) connections (See [guide below](#socks5-guide))
 - Clients optionally allow [SOCKS5](https://en.wikipedia.org/wiki/SOCKS) connections from a reversed port forward
+- Client connections over stdio which supports `ssh -o ProxyCommand` providing SSH over HTTP
 
 ### Install
 
@@ -178,6 +179,7 @@ $ chisel client --help
       R:2222:localhost:22
       R:socks
       R:5000:socks
+      stdio:example.com:22
 
     When the chisel server has --socks5 enabled, remotes can
     specify "socks" in place of remote-host and remote-port.
@@ -193,6 +195,13 @@ $ chisel client --help
     default socks port (1080) and terminate the connection at the
     client's internal SOCKS5 proxy.
 
+    When stdio is used as local-host, the tunnel will connect standard
+    input/output of this program with the remote. This is useful when 
+    combined with ssh ProxyCommand. You can use
+      ssh -o ProxyCommand='chisel client chiselserver stdio:%h:%p' \
+          [email protected]
+    to connect to an SSH server through the tunnel.
+
   Options:
 
     --fingerprint, A *strongly recommended* fingerprint string

client/client.go

@@ -2,6 +2,7 @@ package chclient
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -74,6 +75,7 @@ func NewClient(config *Config) (*Client, error) {
 	u.Scheme = strings.Replace(u.Scheme, "http", "ws", 1)
 	shared := &chshare.Config{}
 	createSocksServer := false
+	hasStdio := false
 	for _, s := range config.Remotes {
 		r, err := chshare.DecodeRemote(s)
 		if err != nil {
@@ -82,6 +84,12 @@ func NewClient(config *Config) (*Client, error) {
 		if r.Socks && r.Reverse {
 			createSocksServer = true
 		}
+		if r.Stdio {
+			if hasStdio {
+				return nil, errors.New("Only one stdio is allowed")
+			}
+			hasStdio = true
+		}
 		shared.Remotes = append(shared.Remotes, r)
 	}
 	config.shared = shared

main.go

@@ -255,6 +255,7 @@ var clientHelp = `
       R:2222:localhost:22
       R:socks
       R:5000:socks
+      stdio:example.com:22
 
     When the chisel server has --socks5 enabled, remotes can
     specify "socks" in place of remote-host and remote-port.
@@ -270,6 +271,13 @@ var clientHelp = `
     default socks port (1080) and terminate the connection at the
     client's internal SOCKS5 proxy.
 
+    When stdio is used as local-host, the tunnel will connect standard
+    input/output of this program with the remote. This is useful when 
+    combined with ssh ProxyCommand. You can use
+      ssh -o ProxyCommand='chisel client chiselserver stdio:%h:%p' \
+          [email protected]
+    to connect to an SSH server through the tunnel.
+
   Options:
 
     --fingerprint, A *strongly recommended* fingerprint string

share/logger.go

@@ -6,7 +6,7 @@ import (
 	"os"
 )
 
-//Logger is ...
+//Logger is pkg/log Logger with prefixing and 2 log levels
 type Logger struct {
 	prefix      string
 	logger      *log.Logger
@@ -20,7 +20,7 @@ func NewLogger(prefix string) *Logger {
 func NewLoggerFlag(prefix string, flag int) *Logger {
 	l := &Logger{
 		prefix: prefix,
-		logger: log.New(os.Stdout, "", flag),
+		logger: log.New(os.Stderr, "", flag),
 		Info:   false,
 		Debug:  false,
 	}

share/proxy.go

@@ -31,15 +31,31 @@ func NewTCPProxy(logger *Logger, ssh GetSSHConn, index int, remote *Remote) *TCP
 }
 
 func (p *TCPProxy) Start(ctx context.Context) error {
+	if p.remote.Stdio {
+		go p.listenStdio(ctx)
+		return nil
+	}
 	l, err := net.Listen("tcp4", p.remote.LocalHost+":"+p.remote.LocalPort)
 	if err != nil {
 		return fmt.Errorf("%s: %s", p.Logger.Prefix(), err)
 	}
-	go p.listen(ctx, l)
+	go p.listenNet(ctx, l)
 	return nil
 }
 
-func (p *TCPProxy) listen(ctx context.Context, l net.Listener) {
+func (p *TCPProxy) listenStdio(ctx context.Context) {
+	for {
+		p.accept(Stdio)
+		select {
+		case <-ctx.Done():
+			return
+		default:
+			// the connection is not ready yet, keep waiting
+		}
+	}
+}
+
+func (p *TCPProxy) listenNet(ctx context.Context, l net.Listener) {
 	p.Infof("Listening")
 	done := make(chan struct{})
 	go func() {

share/remote.go

@@ -20,10 +20,16 @@ import (
 //   192.168.0.1:3000:google.com:80 ->
 //     local  192.168.0.1:3000
 //     remote google.com:80
+//   127.0.0.1:1080:socks
+//     local  127.0.0.1:1080
+//     remote socks
+//   stdio:example.com:22
+//     local  stdio
+//     remote example.com:22
 
 type Remote struct {
 	LocalHost, LocalPort, RemoteHost, RemotePort string
-	Socks, Reverse                               bool
+	Socks, Reverse, Stdio                        bool
 }
 
 const revPrefix = "R:"
@@ -41,11 +47,16 @@ func DecodeRemote(s string) (*Remote, error) {
 	r := &Remote{Reverse: reverse}
 	for i := len(parts) - 1; i >= 0; i-- {
 		p := parts[i]
-		//last part "socks"?
+		//remote portion is socks?
 		if i == len(parts)-1 && p == "socks" {
 			r.Socks = true
 			continue
 		}
+		//local portion is stdio?
+		if i == 0 && p == "stdio" {
+			r.Stdio = true
+			continue
+		}
 		if isPort(p) {
 			if !r.Socks && r.RemotePort == "" {
 				r.RemotePort = p
@@ -80,6 +91,9 @@ func DecodeRemote(s string) (*Remote, error) {
 	if !r.Socks && r.RemoteHost == "" {
 		r.RemoteHost = "0.0.0.0"
 	}
+	if r.Stdio && r.Reverse {
+		return nil, errors.New("stdio cannot be reversed")
+	}
 	return r, nil
 }
 
@@ -106,7 +120,14 @@ func (r *Remote) String() string {
 	if r.Reverse {
 		tag = revPrefix
 	}
-	return tag + r.LocalHost + ":" + r.LocalPort + "=>" + r.Remote()
+	return tag + r.Local() + "=>" + r.Remote()
+}
+
+func (r *Remote) Local() string {
+	if r.Stdio {
+		return "stdio"
+	}
+	return r.LocalHost + ":" + r.LocalPort
 }
 
 func (r *Remote) Remote() string {

share/stdio.go

@@ -0,0 +1,16 @@
+package chshare
+
+import (
+	"io"
+	"io/ioutil"
+	"os"
+)
+
+//Stdio as a ReadWriteCloser
+var Stdio = &struct {
+	io.ReadCloser
+	io.Writer
+}{
+	ioutil.NopCloser(os.Stdin),
+	os.Stdout,
+}