Lua

Open a Custom SSH Channel Type

Demonstrates the Chilkat Ssh.OpenCustomChannel method, which requests a channel whose application-defined type is supplied as the only argument. It returns the channel number, or -1 if the server rejects the channel. The server must implement that channel type.

Background: The SSH protocol allows vendor- and application-specific channel types beyond the standard session and direct-tcpip kinds; by convention these carry an @domain suffix to avoid name collisions. This method is the escape hatch for talking to a server that implements such a type. On rejection, inspect ChannelOpenFailCode to learn why.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Ssh.OpenCustomChannel method, which requests a custom SSH channel whose
-- application-defined type is supplied as the only argument.  It returns the channel number,
-- or -1 if the server rejects the channel.  The server must implement that channel type.

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

-- Request an application-defined channel type.  The server must support it.
local channelType = "my-custom-channel@example.com"
local channelNum = ssh:open_custom_channel(channelType)
if channelNum < 0 then
    print(ssh.last_error_text)
    return
end

print("Opened custom channel: " .. channelNum)

-- The channel is used with the normal channel send, receive, EOF, CLOSE, and release methods.

ssh:disconnect()