Lua

Continue SFTP Keyboard-Interactive Authentication

Demonstrates the Chilkat SFtp.ContinueKeyboardAuth method, which submits a response to a keyboard-interactive prompt. The only argument is the response text; for a request with multiple prompts, an XML response is supplied instead. It returns XML indicating the next prompt or the final result.

Background: This is the second half of the exchange started by StartKeyboardAuth. A server may issue several rounds of prompts, so a robust client loops: submit answers, read the returned XML, and continue until it sees success or failure. On success, remember that InitializeSftp still must be called before any file operation.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SFtp.ContinueKeyboardAuth method, which submits a response to a
-- keyboard-interactive prompt.  The only argument is the response.  For multiple prompts, an
-- XML response is supplied instead.

local sftp = chilkat.SFtp.new()

-- Step 1: Connect the SSH transport.  Port 22 is the usual port.
local port = 22
local success = sftp:connect("sftp.example.com", port)
if not success then
    print(sftp.last_error_text)
    return
end

-- Begin keyboard-interactive authentication to receive the server's prompt(s).
local infoRequestXml = sftp:start_keyboard_auth("mySshLogin")
if not sftp.last_method_success then
    print(sftp.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"

-- Submit the response (typically the password).  The returned XML indicates the next prompt or
-- the final result.
local result = sftp:continue_keyboard_auth(password)
if not sftp.last_method_success then
    print(sftp.last_error_text)
    return
end

print(result)

-- On success, initialize the SFTP subsystem.
success = sftp:initialize_sftp()
if not success then
    print(sftp.last_error_text)
    return
end

sftp:disconnect()