102 lines
2.3 KiB
Markdown
102 lines
2.3 KiB
Markdown
# Streaming keyboard input
|
|
|
|
We use the Gorilla websocket library to handle the websocket connection.
|
|
|
|
Most of the time, we can use the keylogger library (which uses uinput) to effeciently press keys. However, if we need to send a character that keylogger doesn't know about, we can use the xdotool command. xdotool is also useful if one does not want to use root.
|
|
|
|
xdotool spawns a new process for each keypress, so it's not as effecient as keylogger.
|
|
|
|
To specify xdotool usage, the client should send a message with the format `{kb_cmd:xdotool}:message` where message is a utf-8 string.
|
|
|
|
``` go
|
|
--- streaming keyboard input
|
|
|
|
func clientConnected(w http.ResponseWriter, r *http.Request) {
|
|
// regex if string has characters we need to convert to key presses
|
|
characterRegex, _ := regexp.Compile(`[^\x08]\x08|\t|\n`)
|
|
|
|
// find keyboard device, does not require a root permission
|
|
keyboard := keylogger.FindKeyboardDevice()
|
|
|
|
// check if we found a path to keyboard
|
|
if len(keyboard) <= 0 {
|
|
return
|
|
}
|
|
|
|
k, err := keylogger.New(keyboard)
|
|
if err != nil {
|
|
return
|
|
}
|
|
defer k.Close()
|
|
|
|
@{always use xdotool environment variable}
|
|
|
|
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
c, err := upgrader.Upgrade(w, r, nil)
|
|
if err != nil {
|
|
log.Print("upgrade:", err)
|
|
return
|
|
}
|
|
defer c.Close()
|
|
|
|
// get auth token
|
|
_, message, err := c.ReadMessage()
|
|
if err != nil {
|
|
log.Println("read:", err)
|
|
return
|
|
}
|
|
|
|
if auth.CheckAuthToken(string(message)) != nil {
|
|
log.Println("invalid token")
|
|
c.WriteMessage(websocket.TextMessage, []byte("invalid token"))
|
|
return
|
|
}
|
|
c.WriteMessage(websocket.TextMessage, []byte("authenticated"))
|
|
|
|
for {
|
|
_, message, err := c.ReadMessage()
|
|
if err != nil {
|
|
log.Println("read:", err)
|
|
break
|
|
}
|
|
log.Printf("recv: %s", message)
|
|
message_string := string(message)
|
|
if message_string == "" {
|
|
message_string = "\n"
|
|
}
|
|
|
|
@{send keys to system}
|
|
}
|
|
}
|
|
|
|
---
|
|
```
|
|
|
|
# Sending the keys
|
|
|
|
Sending the keys is a bit tricky as we need to manually convert backspace, tab, enter and modifier keys.
|
|
|
|
``` go
|
|
|
|
--- send keys to system
|
|
|
|
|
|
doXDoTool := func(command string, keys string)(err error) {
|
|
var cmd *exec.Cmd
|
|
if command == "type" {
|
|
cmd = exec.Command("xdotool", command, "--delay", "25", keys)
|
|
} else {
|
|
cmd = exec.Command("xdotool", command, keys)
|
|
}
|
|
return cmd.Run()
|
|
}
|
|
|
|
@{handle xdotoool commands}
|
|
|
|
@{do streaming keylogger approach}
|
|
|
|
---
|
|
``` |