PHP Extension

Start SFTP Keyboard-Interactive Authentication

Demonstrates the Chilkat SFtp.StartKeyboardAuth method, which begins keyboard-interactive authentication. The only argument is the login name. It returns XML describing the server's prompts, which are answered with ContinueKeyboardAuth.

Background: Keyboard-interactive is the prompt-driven authentication method: rather than assuming a single password, the server sends one or more questions — a password, a one-time code, a security question — and the client answers each. This is how SFTP supports two-factor and other challenge-response schemes. The returned XML tells you exactly what to ask and whether to mask the input.

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<?php

include("chilkat.php");

$success = false;

//  Demonstrates the SFtp.StartKeyboardAuth method, which begins keyboard-interactive
//  authentication.  The only argument is the login name.  It returns XML describing the server's
//  prompts, which are answered with ContinueKeyboardAuth.

$sftp = new CkSFtp();

//  Step 1: Connect the SSH transport.  Port 22 is the usual port.
$port = 22;
$success = $sftp->Connect('sftp.example.com',$port);
if ($success == false) {
    print $sftp->lastErrorText() . "\n";
    exit;
}

//  Begin keyboard-interactive authentication.  The returned XML describes the server's prompts.
$infoRequestXml = $sftp->startKeyboardAuth('mySshLogin');
if ($sftp->get_LastMethodSuccess() == false) {
    print $sftp->lastErrorText() . "\n";
    exit;
}

print $infoRequestXml . "\n";

//  Answer the prompt(s) with ContinueKeyboardAuth, then call InitializeSftp.

$sftp->Disconnect();

?>