Lua

SFTP Authenticate with Password and Private Key

Demonstrates the Chilkat SFtp.AuthenticatePwPk method, which authenticates with a server that requires both a password and a private key. The arguments are the username, the password, and an SshKey private key.

Note: The private-key path is relative to the application's current working directory. Supply the path to your own key file.

Background: Most servers require either a password or a public key, not both — but some high-security deployments mandate two-factor SSH, combining something you know (the password) with something you have (the key). This method satisfies that policy in one call. As always, the password should come from a secure source rather than a literal in code.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SFtp.AuthenticatePwPk method, which authenticates with a server that requires
-- BOTH a password and a private key.  The 1st argument is the username, the 2nd is the password,
-- and the 3rd is an SshKey private key.

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

-- 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"

-- Load the SSH private key.  LoadText reads the file's text, which is then imported.
local privKey = chilkat.SshKey.new()
local keyText = privKey:load_text("qa_data/id_rsa")
if not privKey.last_method_success then
    print(privKey.last_error_text)
    return
end

success = privKey:from_open_ssh_private_key(keyText)
if not success then
    print(privKey.last_error_text)
    return
end

success = sftp:authenticate_pw_pk("mySshLogin", password, privKey)
if not success then
    print(sftp.last_error_text)
    return
end

-- Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
-- file or directory operations.
success = sftp:initialize_sftp()
if not success then
    print(sftp.last_error_text)
    return
end

print("Authenticated with a password and a private key.")

sftp:disconnect()