has a websocket shell now!

assets/main.js

@@ -31,7 +31,7 @@ function createTerminal() {
   });
 
   term.open(document.getElementById('terminal_view'));
-  term.resize(120, 36);
+  term.resize(122, 37);
 
   const weblinksAddon = new WebLinksAddon.WebLinksAddon();
   term.loadAddon(weblinksAddon);

go.mod

@@ -3,6 +3,7 @@ module github.com/syssecfsu/wsterm
 go 1.17
 
 require (
+	github.com/creack/pty v1.1.17 // indirect
 	github.com/gin-contrib/sse v0.1.0 // indirect
 	github.com/gin-gonic/gin v1.7.7 // indirect
 	github.com/go-playground/locales v0.13.0 // indirect
@@ -17,6 +18,7 @@ require (
 	github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742 // indirect
 	github.com/ugorji/go/codec v1.1.7 // indirect
 	golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 // indirect
-	golang.org/x/sys v0.0.0-20200116001909-b77594299b42 // indirect
+	golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 // indirect
+	golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 // indirect
 	gopkg.in/yaml.v2 v2.2.8 // indirect
 )

go.sum

@@ -1,3 +1,5 @@
+github.com/creack/pty v1.1.17 h1:QeVUsEDNrLBW4tMgZHvxy18sKtr6VI492kBhUfhDJNI=
+github.com/creack/pty v1.1.17/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=
@@ -42,6 +44,10 @@ golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 h1:SrN+KX8Art/Sf4HNj6Zcz06G7VEz+7w9tdXTPOZ7+l4=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 h1:JGgROgKl9N8DuW20oFS5gxc+lE67/N3FcwmBPMe7ArY=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

main.go

@@ -8,8 +8,45 @@ import (
 
 	"github.com/gin-gonic/gin"
 	"github.com/gorilla/websocket"
+
+	"os"
+	"os/exec"
+
+	"github.com/creack/pty"
+	"golang.org/x/term"
 )
 
+func createPty(cmdline string) (*os.File, *term.State, error) {
+	// Create a shell command.
+	cmd := exec.Command(cmdline)
+
+	// Start the command with a pty.
+	ptmx, err := pty.Start(cmd)
+
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Use fixed size, the xterm is initalized as 122x37,
+	// But we set pty to 120x36. Using fullsize will lead
+	// some program to misbehaive.
+	pty.Setsize(ptmx, &pty.Winsize{
+		Cols: 120,
+		Rows: 36,
+	})
+
+	// Set stdin in raw mode. This might cause problems in ssh.
+	// ignore the error if it so happens
+	termState, err := term.MakeRaw(int(os.Stdin.Fd()))
+
+	if err != nil {
+		fmt.Println(err)
+		return ptmx, nil, err
+	}
+
+	return ptmx, termState, nil
+}
+
 var host *string = nil
 
 var upgrader = websocket.Upgrader{
@@ -42,15 +79,56 @@ func wsHandler(w http.ResponseWriter, r *http.Request) {
 
 	fmt.Println("Created the websocket")
 
+	ptmx, termState, err := createPty("bash")
+
+	defer func() {
+		//close the terminal and restore the terminal state
+		if termState != nil {
+			term.Restore(int(os.Stdin.Fd()), termState)
+		}
+	}()
+
+	if err != nil {
+		fmt.Println("failed to create PTY", err)
+		return
+	}
+
+	// pipe the msgs from WS to pty, we need to use goroutine here
+	go func() {
+		for {
+			_, buf, err := conn.ReadMessage()
+
+			if err != nil {
+				fmt.Println(err)
+				// We need to close pty so the goroutine and this one can end
+				// using defer will cause problems
+				ptmx.Close()
+				return
+			}
+
+			_, err = ptmx.Write(buf)
+
+			if err != nil {
+				fmt.Println(err)
+				ptmx.Close()
+				return
+			}
+		}
+	}()
+
+	readBuf := make([]byte, 4096)
+
 	for {
-		msgType, p, err := conn.ReadMessage()
+		n, err := ptmx.Read(readBuf)
 
 		if err != nil {
 			fmt.Println(err)
+			ptmx.Close()
 			return
 		}
 
-		if err := conn.WriteMessage(msgType, p); err != nil {
+		if err = conn.WriteMessage(websocket.BinaryMessage, readBuf[:n]); err != nil {
+			ptmx.Close()
 			fmt.Println(err)
 			return
 		}