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f2538f337d85695cd6bfa183195ca3189d45d58c
noVNC/utils/wstelnet.js
Joel Martin f2538f337d wsproxy, wstelnet: wrap command, WS telnet client. 
wswrapper:

    Getting the wswrapper.c LD_PRELOAD model working has turned out to
    involve too many dark corners of the glibc/POSIX file descriptor
    space. I realized that 95% of what I want can be accomplished by
    adding a "wrap command" mode to wsproxy.

    The code is still there for now, but consider it experimental at
    best. Minor fix to dup2 and add dup and dup3 logging.

wsproxy Wrap Command:

    In wsproxy wrap command mode, a command line is specified instead
    of a target address and port. wsproxy then uses a much simpler
    LD_PRELOAD library, rebind.so, to move intercept any bind() system
    calls made by the program. If the bind() call is for the wsproxy
    listen port number then the real bind() system call is issued for
    an alternate (free high) port on loopback/localhost.  wsproxy then
    forwards from the listen address/port to the moved port.

    The --wrap-mode argument takes three options that determine the
    behavior of wsproxy when the wrapped command returns an exit code
    (exit or daemonizing): ignore, exit, respawn.

    For example, this runs vncserver on turns port 5901 into
    a WebSockets port (rebind.so must be built first):

        ./utils/wsproxy.py --wrap-mode=ignore 5901 -- vncserver :1

    The vncserver command backgrounds itself so the wrap mode is set
    to "ignore" so that wsproxy keeps running even after it receives
    an exit code from vncserver.

wstelnet:

    To demonstrate the wrap command mode, I added WebSockets telnet
    client.

    For example, this runs telnetd (krb5-telnetd) on turns port 2023
    into a WebSockets port (using "respawn" mode since telnetd exits
    after each connection closes):

        sudo ./utils/wsproxy.py --wrap-mode=respawn 2023 -- telnetd -debug 2023

    Then the utils/wstelnet.html page can be used to connect to the
    telnetd server on port 2023. The telnet client includes VT100.js
    (from http://code.google.com/p/sshconsole) which handles the
    terminal emulation and rendering.

rebind:

    The rebind LD_PRELOAD library is used by wsproxy in wrap command
    mode to intercept bind() system calls and move the port to
    a different port on loopback/localhost. The rebind.so library can
    be built by running make in the utils directory.

    The rebind library can be used separately from wsproxy by setting
    the REBIND_OLD_PORT and REBIND_NEW_PORT environment variables
    prior to executing a command. For example:

        export export REBIND_PORT_OLD="23"
        export export REBIND_PORT_NEW="65023"
        LD_PRELOAD=./rebind.so telnetd -debug 23

    Alternately, the rebind script does the same thing:

        rebind 23 65023 telnetd -debug 23

Other changes/notes:

- wsproxy no longer daemonizes by default. Remove -f/--foreground
  option and add -D/--deamon option.

- When wsproxy is used to wrap a command in "respawn" mode, the
  command will not be respawn more often than 3 times within 10
  seconds.

- Move getKeysym routine out of Canvas object so that it can be called
  directly.
2011-01-12 13:15:11 -06:00

334 lines
9.2 KiB
JavaScript
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/*
* WebSockets telnet client
* Copyright (C) 2011 Joel Martin
* Licensed under LGPL-3 (see LICENSE.txt)
*
* Incorporates VT100.js from:
* http://code.google.com/p/sshconsole
* Which was modified from:
* http://fzort.org/bi/o.php#vt100_js
*
* Telnet protocol:
* http://www.networksorcery.com/enp/protocol/telnet.htm
* http://www.networksorcery.com/enp/rfc/rfc1091.txt
*
* ANSI escape sequeneces:
* http://en.wikipedia.org/wiki/ANSI_escape_code
* http://ascii-table.com/ansi-escape-sequences-vt-100.php
* http://www.termsys.demon.co.uk/vtansi.htm
* http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
*
* ASCII codes:
* http://en.wikipedia.org/wiki/ASCII
* http://www.hobbyprojects.com/ascii-table/ascii-table.html
*
* Other web consoles:
* http://stackoverflow.com/questions/244750/ajax-console-window-with-ansi-vt100-support
*/
function Telnet(target, connect_callback, disconnect_callback) {
var that = {}, // Public API interface
vt100, ws, sQ = [];
termType = "VT100";
Array.prototype.pushStr = function (str) {
var n = str.length;
for (var i=0; i < n; i++) {
this.push(str.charCodeAt(i));
}
}
function do_send() {
if (sQ.length > 0) {
Util.Debug("Sending " + sQ);
ws.send(Base64.encode(sQ));
sQ = [];
}
}
function do_recv(e) {
//console.log(">> do_recv");
var arr = Base64.decode(e.data), str = "",
chr, cmd, code, value;
Util.Debug("Received array '" + arr + "'");
while (arr.length > 0) {
chr = arr.shift();
switch (chr) {
case 255: // IAC
cmd = chr;
code = arr.shift();
value = arr.shift();
switch (code) {
case 254: // DONT
Util.Debug("Got Cmd DONT '" + value + "', ignoring");
break;
case 253: // DO
Util.Debug("Got Cmd DO '" + value + "'");
if (value === 24) {
// Terminal type
Util.Info("Send WILL '" + value + "' (TERM-TYPE)");
sQ.push(255, 251, value);
} else {
// Refuse other DO requests with a WONT
Util.Debug("Send WONT '" + value + "'");
sQ.push(255, 252, value);
}
break;
case 252: // WONT
Util.Debug("Got Cmd WONT '" + value + "', ignoring");
break;
case 251: // WILL
Util.Debug("Got Cmd WILL '" + value + "'");
if (value === 1) {
// Affirm echo with DO
Util.Info("Send Cmd DO '" + value + "' (echo)");
sQ.push(255, 253, value);
} else {
// Reject other WILL offers with a DONT
Util.Debug("Send Cmd DONT '" + value + "'");
sQ.push(255, 254, value);
}
break;
case 250: // SB (subnegotiation)
if (value === 24) {
Util.Info("Got IAC SB TERM-TYPE SEND(1) IAC SE");
// TERM-TYPE subnegotiation
if (arr[0] === 1 &&
arr[1] === 255 &&
arr[2] === 240) {
arr.shift(); arr.shift(); arr.shift();
Util.Info("Send IAC SB TERM-TYPE IS(0) '" +
termType + "' IAC SE");
sQ.push(255, 250, 24, 0);
sQ.pushStr(termType);
sQ.push(255, 240);
} else {
Util.Info("Invalid subnegotiation received" + arr);
}
} else {
Util.Info("Ignoring SB " + value);
}
break;
default:
Util.Info("Got Cmd " + cmd + " " + value + ", ignoring"); }
continue;
case 242: // Data Mark (Synch)
cmd = chr;
code = arr.shift();
value = arr.shift();
Util.Info("Ignoring Data Mark (Synch)");
break;
default: // everything else
str += String.fromCharCode(chr);
}
}
if (sQ) {
do_send();
}
if (str) {
vt100.write(str);
}
//console.log("<< do_recv");
}
that.connect = function(host, port, encrypt) {
var host = host,
port = port,
scheme = "ws://", uri;
Util.Debug(">> connect");
if ((!host) || (!port)) {
console.log("must set host and port");
return;
}
if (ws) {
ws.close();
}
if (encrypt) {
scheme = "wss://";
}
uri = scheme + host + ":" + port;
Util.Info("connecting to " + uri);
ws = new WebSocket(uri);
ws.onmessage = do_recv;
ws.onopen = function(e) {
Util.Info(">> WebSockets.onopen");
vt100.curs_set(true, true);
connect_callback();
Util.Info("<< WebSockets.onopen");
};
ws.onclose = function(e) {
Util.Info(">> WebSockets.onclose");
that.disconnect();
Util.Info("<< WebSockets.onclose");
};
ws.onerror = function(e) {
Util.Info(">> WebSockets.onerror");
that.disconnect();
Util.Info("<< WebSockets.onerror");
};
Util.Debug("<< connect");
}
that.disconnect = function() {
Util.Debug(">> disconnect");
if (ws) {
ws.close();
}
vt100.curs_set(true, false);
disconnect_callback();
Util.Debug("<< disconnect");
}
function constructor() {
/* Initialize the terminal emulator/renderer */
vt100 = new VT100(80, 24, target);
// Turn off local echo
vt100.noecho();
/*
* Override VT100 I/O routines
*/
// Set handler for sending characters
vt100.getch(
function send_chr(chr, vt) {
var i;
Util.Debug(">> send_chr: " + chr);
for (i = 0; i < chr.length; i++) {
sQ.push(chr.charCodeAt(i));
}
do_send();
vt100.getch(send_chr);
}
);
vt100.debug = function(message) {
Util.Debug(message + "\n");
}
vt100.warn = function(message) {
Util.Warn(message + "\n");
}
vt100.curs_set = function(vis, grab, eventist)
{
this.debug("curs_set:: vis: " + vis + ", grab: " + grab);
if (vis !== undefined)
this.cursor_vis_ = (vis > 0);
if (eventist === undefined)
eventist = window;
if (grab === true || grab === false) {
if (grab === this.grab_events_)
return;
if (grab) {
this.grab_events_ = true;
VT100.the_vt_ = this;
Util.addEvent(eventist, 'keydown', vt100.key_down);
Util.addEvent(eventist, 'keyup', vt100.key_up);
} else {
Util.removeEvent(eventist, 'keydown', vt100.key_down);
Util.removeEvent(eventist, 'keyup', vt100.key_up);
this.grab_events_ = false;
VT100.the_vt_ = undefined;
}
}
}
vt100.key_down = function(e) {
var vt = VT100.the_vt_, keysym, ch, str = "";
if (vt === undefined)
return true;
keysym = getKeysym(e);
if (keysym < 128) {
if (e.ctrlKey) {
if (keysym == 64) {
// control 0
ch = 0;
} else if ((keysym >= 97) && (keysym <= 122)) {
// control codes 1-26
ch = keysym - 96;
} else if ((keysym >= 91) && (keysym <= 95)) {
// control codes 27-31
ch = keysym - 64;
} else {
Util.Info("Debug unknown control keysym: " + keysym);
}
} else {
ch = keysym;
}
str = String.fromCharCode(ch);
} else {
switch (keysym) {
case 65505: // Shift, do not send directly
break;
case 65507: // Ctrl, do not send directly
break;
case 65293: // Carriage return, line feed
str = '\n'; break;
case 65288: // Backspace
str = '\b'; break;
case 65307: // Escape
str = '\x1b'; break;
case 65361: // Left arrow
str = '\x1b[D'; break;
case 65362: // Up arrow
str = '\x1b[A'; break;
case 65363: // Right arrow
str = '\x1b[C'; break;
case 65364: // Down arrow
str = '\x1b[B'; break;
default:
Util.Info("Unrecoginized keysym " + keysym);
}
}
if (str) {
vt.key_buf_.push(str);
setTimeout(VT100.go_getch_, 0);
}
Util.stopEvent(e);
return false;
}
vt100.key_up = function(e) {
var vt = VT100.the_vt_;
if (vt === undefined)
return true;
Util.stopEvent(e);
return false;
}
return that;
}
return constructor(); // Return the public API interface
} // End of Telnet()
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