Lua

SSH Tunnel Authenticate with Password and Private Key

Demonstrates the Chilkat SshTunnel.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. Absolute paths may also be used. 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. This method satisfies that policy in one call, combining something you know (the password) with something you have (the key). The password should come from a secure source rather than a literal.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SshTunnel.AuthenticatePwPk method, which authenticates with an SSH 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 tunnel = chilkat.SshTunnel.new()

-- The tunnel forwards accepted local connections to this destination through the SSH server.
tunnel.dest_hostname = "db.internal.example.com"
tunnel.dest_port = 5432

-- Connect to the SSH server.  This performs the TCP/proxy connection and SSH handshake, but
-- does not authenticate yet.
local sshPort = 22
local success = tunnel:connect("ssh.example.com", sshPort)
if not success then
    print(tunnel.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 = tunnel:authenticate_pw_pk("mySshLogin", password, privKey)
if not success then
    print(tunnel.last_error_text)
    return
end

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

-- After authenticating, call BeginAccepting to start listening for local connections to forward.

local waitForThreadExit = true
success = tunnel:close_tunnel(waitForThreadExit)
if not success then
    print(tunnel.last_error_text)
    return
end