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Continue SSH Tunnel Keyboard-Interactive Authentication

Demonstrates the Chilkat SshTunnel.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, BeginAccepting still must be called before the tunnel forwards traffic.

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

#  Demonstrates the SshTunnel.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.

$tunnel = New-Object Chilkat.SshTunnel

#  The tunnel forwards accepted local connections to this destination through the SSH server.
$tunnel.DestHostname = "db.internal.example.com"
$tunnel.DestPort = 5432

#  Connect to the SSH server.  This performs the TCP/proxy connection and SSH handshake, but
#  does not authenticate yet.
$sshPort = 22
$success = $tunnel.Connect("ssh.example.com",$sshPort)
if ($success -eq $false) {
    $($tunnel.LastErrorText)
    exit
}

#  Begin keyboard-interactive authentication to receive the server's prompt(s).
$infoRequestXml = $tunnel.StartKeyboardAuth("mySshLogin")
if ($tunnel.LastMethodSuccess -eq $false) {
    $($tunnel.LastErrorText)
    exit
}

#  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.
$password = "mySshPassword"

#  Submit the response (typically the password).  The returned XML indicates the next prompt or
#  the final result.
$result = $tunnel.ContinueKeyboardAuth($password)
if ($tunnel.LastMethodSuccess -eq $false) {
    $($tunnel.LastErrorText)
    exit
}

$($result)

$waitForThreadExit = $true
$success = $tunnel.CloseTunnel($waitForThreadExit)
if ($success -eq $false) {
    $($tunnel.LastErrorText)
    exit
}