Lua

Request SSH X11 Forwarding

Demonstrates the Chilkat Ssh.SendReqX11Forwarding method, which sends an X11-forwarding request on a session channel. The arguments are the channel number, whether forwarding is limited to a single connection, and the X11 authentication protocol, cookie, and screen number.

Background: X11 forwarding lets a graphical program running on the remote host display its window on your local machine, tunneled over SSH. This is a low-level method that only sends the protocol request — your application is still responsible for the local X server side of the arrangement. The authentication cookie guards the forwarded display, so it should be a freshly generated value rather than a fixed constant.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Ssh.SendReqX11Forwarding method, which sends an SSH X11-forwarding request
-- on a session channel.  The 1st argument is the channel number, the 2nd limits forwarding to a
-- single connection, and the 3rd through 5th supply the X11 authentication protocol, cookie,
-- and screen number.

local ssh = chilkat.Ssh.new()

local sshPort = 22
local success = ssh:connect("ssh.example.com", sshPort)
if not success then
    print(ssh.last_error_text)
    return
end

-- Normally you would not hard-code the password in source.  You should instead obtain it
-- from an interactive prompt, environment variable, or a secrets vault.
local password = "mySshPassword"

success = ssh:authenticate_pw("mySshLogin", password)
if not success then
    print(ssh.last_error_text)
    return
end

-- Open a session channel.  A negative return value indicates failure.
local channelNum = ssh:open_session_channel()
if channelNum < 0 then
    print(ssh.last_error_text)
    return
end

-- Request X11 forwarding.  Named variables make each argument's meaning clear.
local singleConnection = false
local authProt = "MIT-MAGIC-COOKIE-1"
local authCookie = "d92f5e1a7c8b4306af17c2e5b9d43081"
local screenNum = 0
success = ssh:send_req_x11_forwarding(channelNum, singleConnection, authProt, authCookie, screenNum)
if not success then
    print(ssh.last_error_text)
    return
end

print("X11 forwarding requested.")

ssh:disconnect()