uskbdxrdp.go

// uskbdxrdp
// MIT License Copyright(c) 2020 Hiroshi Shimamoto
// vim:set sw=4 sts=4:

package main

import (
    "log"
    "net"

    "github.com/hshimamoto/go-session"
    "github.com/hshimamoto/go-iorelay"
)

func handler(conn net.Conn) {
    defer conn.Close()
    log.Println("connected")
    fconn, err := session.Dial("127.0.0.1:3389")
    if err != nil {
        log.Printf("Connect failed: %v\n", err)
        return
    }
    { // -> hello
        buf := make([]byte, 4096)
        n, _ := conn.Read(buf)
        fconn.Write(buf[:n])
    }
    { // <- hello
        buf := make([]byte, 4096)
        n, _ :=fconn.Read(buf)
        conn.Write(buf[:n])
    }
    { // -> params
        buf := make([]byte, 4096)
        n, _ := conn.Read(buf)
        if n > 0x100 {
            //        0  1  2  3  4  5  6  7  8  9  a  b  c
            // 0090: 00 a0 05 84 03 01 ca 03 aa 11 04 01 e0 28 0a 00
            // ->
            // 0090: 00 a0 05 84 03 01 ca 03 aa 09 04 00 00 28 0a 00
            for x := 0x40; x < 0x100; x++ {
                if buf[x] == 0x03 && buf[x+1] == 0xaa {
                    buf[x+2] = 0x09
                    buf[x+3] = 0x04
                    buf[x+4] = 0x00
                    buf[x+5] = 0x00
                    log.Printf("@0x%x: force us kbd", x)
                    break
                }
            }
        }
        fconn.Write(buf[:n])
    }
    iorelay.Relay(conn, fconn)
}

func main() {
    s, err := session.NewServer(":3390", handler)
    if err != nil {
        log.Printf("session.NewServer: %v\n", err)
        return
    }
    s.Run()
}